diff --git a/composer.json b/composer.json
index 51ae66ea..2c9a6c6a 100644
--- a/composer.json
+++ b/composer.json
@@ -39,7 +39,10 @@
     "scripts": {
         "ci:phpcs": "phpcs -q --report=checkstyle | cs2pr",
         "ci:psalm": "psalm --output-format=github --shepherd --stats",
-        "ci:coverage": "paratest --coverage-clover dist/phpunit/clover.xml",
+        "ci:coverage": [
+            "Composer\\Config::disableProcessTimeout",
+            "paratest --coverage-clover dist/phpunit/clover.xml"
+        ],
         "ci:unit": "paratest --testsuite Unit",
         "ci:integration": "paratest --testsuite Integration",
         "ci:mutation": [
@@ -53,7 +56,7 @@
         ],
         "test:phpcs": "phpcs",
         "test:psalm": "psalm --no-cache",
-        "test:unit": "paratest --testsuite Unit",
+        "test:unit": "phpunit --testsuite Unit",
         "test:integration": "paratest --testsuite Integration",
         "test:coverage": "paratest --coverage-html dist/phpunit/html && echo \"Open the result on your browser: $PWD/dist/phpunit/html/index.html\""
     },
diff --git a/src/Blocks/BulletedListItem.php b/src/Blocks/BulletedListItem.php
index affd65ba..3e70bace 100644
--- a/src/Blocks/BulletedListItem.php
+++ b/src/Blocks/BulletedListItem.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Common\RichText;
 
 /**
@@ -13,6 +14,7 @@
  * @psalm-type BulletedListItemJson = array{
  *      bulleted_list_item: array{
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children?: list<BlockMetadataJson>,
  *      },
  * }
@@ -28,6 +30,7 @@ class BulletedListItem implements BlockInterface
     private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $this->metadata->checkType(BlockType::BulletedListItem);
@@ -40,7 +43,7 @@ public static function create(): self
     {
         $metadata = BlockMetadata::create(BlockType::BulletedListItem);
 
-        return new self($metadata, [], []);
+        return new self($metadata, [], Color::Default, []);
     }
 
     /**
@@ -51,7 +54,7 @@ public static function fromString(string $content): self
         $metadata = BlockMetadata::create(BlockType::BulletedListItem);
         $text = [ RichText::fromString($content) ];
 
-        return new self($metadata, $text, []);
+        return new self($metadata, $text, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -64,9 +67,11 @@ public static function fromArray(array $array): self
 
         $text = array_map(fn($t) => RichText::fromArray($t), $item["rich_text"]);
 
+        $color = Color::tryFrom($item["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $item["children"] ?? []);
 
-        return new self($metadata, $text, $children);
+        return new self($metadata, $text, $color, $children);
     }
 
     public function toArray(): array
@@ -75,6 +80,7 @@ public function toArray(): array
 
         $array["bulleted_list_item"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
+            "color"     => $this->color->value,
             "children"  => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
@@ -94,7 +100,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata->update(), $text, $this->children);
+        return new self($this->metadata->update(), $text, $this->color, $this->children);
     }
 
     /**
@@ -105,7 +111,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->children);
+        return new self($this->metadata, $texts, $this->color, $this->children);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -115,6 +121,7 @@ public function changeChildren(BlockInterface ...$children): self
         return new self(
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
+            $this->color,
             $children,
         );
     }
@@ -127,15 +134,27 @@ public function addChild(BlockInterface $child): self
         return new self(
             $this->metadata->updateHasChildren(true),
             $this->text,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Callout.php b/src/Blocks/Callout.php
index cede3e61..5668ccb1 100644
--- a/src/Blocks/Callout.php
+++ b/src/Blocks/Callout.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Common\Emoji;
 use Notion\Common\File;
 use Notion\Common\Icon;
@@ -16,6 +17,7 @@
  * @psalm-type CalloutJson = array{
  *      callout: array{
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children?: list<BlockMetadataJson>,
  *          icon: EmojiJson|FileJson,
  *      },
@@ -33,6 +35,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly Icon $icon,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $metadata->checkType(BlockType::Callout);
@@ -43,7 +46,7 @@ public static function create(): self
         $metadata = BlockMetadata::create(BlockType::Callout);
         $icon = Icon::fromEmoji(Emoji::fromString("⭐"));
 
-        return new self($metadata, [], $icon, []);
+        return new self($metadata, [], $icon, Color::Default, []);
     }
 
     public static function fromString(string $emoji, string $content): self
@@ -52,7 +55,7 @@ public static function fromString(string $emoji, string $content): self
         $text = [ RichText::fromString($content) ];
         $icon = Icon::fromEmoji(Emoji::fromString($emoji));
 
-        return new self($metadata, $text, $icon, []);
+        return new self($metadata, $text, $icon, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -76,9 +79,11 @@ public static function fromArray(array $array): self
             $icon = Icon::fromFile($file);
         }
 
+        $color = Color::tryFrom($callout["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $callout["children"] ?? []);
 
-        return new self($metadata, $text, $icon, $children);
+        return new self($metadata, $text, $icon, $color, $children);
     }
 
     public function toArray(): array
@@ -88,6 +93,7 @@ public function toArray(): array
         $array["callout"] = [
             "rich_text"     => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "icon"     => $this->icon->toArray(),
+            "color"    => $this->color->value,
             "children" => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
@@ -106,7 +112,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->icon, $this->children);
+        return new self($this->metadata, $text, $this->icon, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -114,7 +120,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->icon, $this->children);
+        return new self($this->metadata, $texts, $this->icon, $this->color, $this->children);
     }
 
     public function changeIcon(Emoji|File|Icon $icon): self
@@ -127,7 +133,7 @@ public function changeIcon(Emoji|File|Icon $icon): self
             $icon = Icon::fromFile($icon);
         }
 
-        return new self($this->metadata, $this->text, $icon, $this->children);
+        return new self($this->metadata, $this->text, $icon, $this->color, $this->children);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -138,6 +144,7 @@ public function changeChildren(BlockInterface ...$children): self
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
             $this->icon,
+            $this->color,
             $children,
         );
     }
@@ -151,16 +158,29 @@ public function addChild(BlockInterface $child): self
             $this->metadata->updateHasChildren(true),
             $this->text,
             $this->icon,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->icon,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
             $this->icon,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Heading1.php b/src/Blocks/Heading1.php
index 85d1cfd1..7f6cfcae 100644
--- a/src/Blocks/Heading1.php
+++ b/src/Blocks/Heading1.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -14,6 +15,7 @@
  *      heading_1: array{
  *          rich_text: RichTextJson[],
  *          is_toggleable: bool,
+ *          color?: string,
  *          children?: BlockMetadataJson[]
  *      },
  * }
@@ -30,6 +32,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly bool $isToggleable,
+        public readonly Color $color,
         public readonly array|null $children,
     ) {
         $metadata->checkType(BlockType::Heading1);
@@ -39,7 +42,7 @@ public static function fromText(RichText ...$text): self
     {
         $block = BlockMetadata::create(BlockType::Heading1);
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -47,7 +50,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Heading1);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -62,12 +65,14 @@ public static function fromArray(array $array): self
 
         $isToggleable = $heading["is_toggleable"];
 
+        $color = Color::tryFrom($heading["color"] ?? "") ?? Color::Default;
+
         $children = null;
         if ($isToggleable) {
             $children = array_map(fn($b) => BlockFactory::fromArray($b), $heading["children"] ?? []);
         }
 
-        return new self($block, $text, $isToggleable, $children);
+        return new self($block, $text, $isToggleable, $color, $children);
     }
 
     public function toArray(): array
@@ -77,6 +82,7 @@ public function toArray(): array
         $array["heading_1"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "is_toggleable" => $this->isToggleable,
+            "color" => $this->color->value,
             "children" => array_map(fn($b) => $b->toArray(), $this->children ?? [])
         ];
 
@@ -100,7 +106,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->isToggleable, $this->children);
+        return new self($this->metadata, $text, $this->isToggleable, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -108,12 +114,12 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->isToggleable, $this->children);
+        return new self($this->metadata, $texts, $this->isToggleable, $this->color, $this->children);
     }
 
     public function toggllify(): self
     {
-        return new self($this->metadata, $this->text, true, []);
+        return new self($this->metadata, $this->text, true, $this->color, []);
     }
 
     public function untogglify(): self
@@ -122,7 +128,18 @@ public function untogglify(): self
             throw HeadingException::untogglifyWithChildren();
         }
 
-        return new self($this->metadata, $this->text, false, null);
+        return new self($this->metadata, $this->text, false, $this->color, null);
+    }
+
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->isToggleable,
+            $color,
+            $this->children,
+        );
     }
 
     public function addChild(BlockInterface $child): self
@@ -136,6 +153,7 @@ public function addChild(BlockInterface $child): self
             $this->metadata,
             $this->text,
             $this->isToggleable,
+            $this->color,
             $children,
         );
     }
@@ -146,7 +164,7 @@ public function changeChildren(BlockInterface ...$children): self
             throw BlockException::noChindrenSupport();
         }
 
-        return new self($this->metadata, $this->text, $this->isToggleable, $children);
+        return new self($this->metadata, $this->text, $this->isToggleable, $this->color, $children);
     }
 
     public function archive(): BlockInterface
@@ -155,6 +173,7 @@ public function archive(): BlockInterface
             $this->metadata->archive(),
             $this->text,
             $this->isToggleable,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Heading2.php b/src/Blocks/Heading2.php
index 89456125..c93b8d1b 100644
--- a/src/Blocks/Heading2.php
+++ b/src/Blocks/Heading2.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -14,6 +15,7 @@
  *      heading_2: array{
  *          rich_text: RichTextJson[],
  *          is_toggleable: bool,
+ *          color?: string,
  *          children?: BlockMetadataJson[]
  *      },
  * }
@@ -30,6 +32,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly bool $isToggleable,
+        public readonly Color $color,
         public readonly array|null $children,
     ) {
         $metadata->checkType(BlockType::Heading2);
@@ -39,7 +42,7 @@ public static function fromText(RichText ...$text): self
     {
         $block = BlockMetadata::create(BlockType::Heading2);
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -47,7 +50,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Heading2);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -62,12 +65,14 @@ public static function fromArray(array $array): self
 
         $isToggleable = $heading["is_toggleable"];
 
+        $color = Color::tryFrom($heading["color"] ?? "") ?? Color::Default;
+
         $children = null;
         if ($isToggleable) {
             $children = array_map(fn($b) => BlockFactory::fromArray($b), $heading["children"] ?? []);
         }
 
-        return new self($block, $text, $isToggleable, $children);
+        return new self($block, $text, $isToggleable, $color, $children);
     }
 
     public function toArray(): array
@@ -77,6 +82,7 @@ public function toArray(): array
         $array["heading_2"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "is_toggleable" => $this->isToggleable,
+            "color" => $this->color->value,
             "children" => array_map(fn($b) => $b->toArray(), $this->children ?? [])
         ];
 
@@ -100,7 +106,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->isToggleable, $this->children);
+        return new self($this->metadata, $text, $this->isToggleable, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -108,12 +114,12 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->isToggleable, $this->children);
+        return new self($this->metadata, $texts, $this->isToggleable, $this->color, $this->children);
     }
 
     public function toggllify(): self
     {
-        return new self($this->metadata, $this->text, true, []);
+        return new self($this->metadata, $this->text, true, $this->color, []);
     }
 
     public function untogglify(): self
@@ -122,7 +128,18 @@ public function untogglify(): self
             throw HeadingException::untogglifyWithChildren();
         }
 
-        return new self($this->metadata, $this->text, false, null);
+        return new self($this->metadata, $this->text, false, $this->color, null);
+    }
+
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->isToggleable,
+            $color,
+            $this->children,
+        );
     }
 
     public function addChild(BlockInterface $child): self
@@ -136,6 +153,7 @@ public function addChild(BlockInterface $child): self
             $this->metadata,
             $this->text,
             $this->isToggleable,
+            $this->color,
             $children,
         );
     }
@@ -146,7 +164,7 @@ public function changeChildren(BlockInterface ...$children): self
             throw BlockException::noChindrenSupport();
         }
 
-        return new self($this->metadata, $this->text, $this->isToggleable, $children);
+        return new self($this->metadata, $this->text, $this->isToggleable, $this->color, $children);
     }
 
     public function archive(): BlockInterface
@@ -155,6 +173,7 @@ public function archive(): BlockInterface
             $this->metadata->archive(),
             $this->text,
             $this->isToggleable,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Heading3.php b/src/Blocks/Heading3.php
index 329c8f80..96ada800 100644
--- a/src/Blocks/Heading3.php
+++ b/src/Blocks/Heading3.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -14,6 +15,7 @@
  *      heading_3: array{
  *          rich_text: RichTextJson[],
  *          is_toggleable: bool,
+ *          color?: string,
  *          children?: BlockMetadataJson[]
  *      },
  * }
@@ -30,6 +32,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly bool $isToggleable,
+        public readonly Color $color,
         public readonly array|null $children,
     ) {
         $metadata->checkType(BlockType::Heading3);
@@ -39,7 +42,7 @@ public static function fromText(RichText ...$text): self
     {
         $block = BlockMetadata::create(BlockType::Heading3);
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -47,7 +50,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Heading3);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -62,12 +65,14 @@ public static function fromArray(array $array): self
 
         $isToggleable = $heading["is_toggleable"];
 
+        $color = Color::tryFrom($heading["color"] ?? "") ?? Color::Default;
+
         $children = null;
         if ($isToggleable) {
             $children = array_map(fn($b) => BlockFactory::fromArray($b), $heading["children"] ?? []);
         }
 
-        return new self($block, $text, $isToggleable, $children);
+        return new self($block, $text, $isToggleable, $color, $children);
     }
 
     public function toArray(): array
@@ -77,6 +82,7 @@ public function toArray(): array
         $array["heading_3"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "is_toggleable" => $this->isToggleable,
+            "color" => $this->color->value,
             "children" => array_map(fn($b) => $b->toArray(), $this->children ?? [])
         ];
 
@@ -100,7 +106,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->isToggleable, $this->children);
+        return new self($this->metadata, $text, $this->isToggleable, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -108,12 +114,12 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->isToggleable, $this->children);
+        return new self($this->metadata, $texts, $this->isToggleable, $this->color, $this->children);
     }
 
     public function toggllify(): self
     {
-        return new self($this->metadata, $this->text, true, []);
+        return new self($this->metadata, $this->text, true, $this->color, []);
     }
 
     public function untogglify(): self
@@ -122,7 +128,18 @@ public function untogglify(): self
             throw HeadingException::untogglifyWithChildren();
         }
 
-        return new self($this->metadata, $this->text, false, null);
+        return new self($this->metadata, $this->text, false, $this->color, null);
+    }
+
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->isToggleable,
+            $color,
+            $this->children,
+        );
     }
 
     public function addChild(BlockInterface $child): self
@@ -136,6 +153,7 @@ public function addChild(BlockInterface $child): self
             $this->metadata,
             $this->text,
             $this->isToggleable,
+            $this->color,
             $children,
         );
     }
@@ -146,7 +164,7 @@ public function changeChildren(BlockInterface ...$children): self
             throw BlockException::noChindrenSupport();
         }
 
-        return new self($this->metadata, $this->text, $this->isToggleable, $children);
+        return new self($this->metadata, $this->text, $this->isToggleable, $this->color, $children);
     }
 
     public function archive(): BlockInterface
@@ -155,6 +173,7 @@ public function archive(): BlockInterface
             $this->metadata->archive(),
             $this->text,
             $this->isToggleable,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/NumberedListItem.php b/src/Blocks/NumberedListItem.php
index abd281a0..17106548 100644
--- a/src/Blocks/NumberedListItem.php
+++ b/src/Blocks/NumberedListItem.php
@@ -2,7 +2,7 @@
 
 namespace Notion\Blocks;
 
-use Notion\Exceptions\BlockException;
+use Notion\Common\Color;
 use Notion\Common\RichText;
 
 /**
@@ -12,6 +12,7 @@
  * @psalm-type NumberedListItemJson = array{
  *      numbered_list_item: array{
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children?: list<BlockMetadataJson>,
  *      },
  * }
@@ -27,6 +28,7 @@ class NumberedListItem implements BlockInterface
     private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $metadata->checkType(BlockType::NumberedListItem);
@@ -36,7 +38,7 @@ public static function create(): self
     {
         $block = BlockMetadata::create(BlockType::NumberedListItem);
 
-        return new self($block, [], []);
+        return new self($block, [], Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -44,7 +46,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::NumberedListItem);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, []);
+        return new self($block, $text, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -57,9 +59,11 @@ public static function fromArray(array $array): self
 
         $text = array_map(fn($t) => RichText::fromArray($t), $item["rich_text"]);
 
+        $color = Color::tryFrom($item["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $item["children"] ?? []);
 
-        return new self($block, $text, $children);
+        return new self($block, $text, $color, $children);
     }
 
     public function toArray(): array
@@ -68,6 +72,7 @@ public function toArray(): array
 
         $array["numbered_list_item"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
+            "color"     => $this->color->value,
             "children"  => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
@@ -86,7 +91,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata->update(), $text, $this->children);
+        return new self($this->metadata->update(), $text, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -94,7 +99,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata->update(), $texts, $this->children);
+        return new self($this->metadata->update(), $texts, $this->color, $this->children);
     }
 
     public function addChild(BlockInterface $child): self
@@ -105,6 +110,7 @@ public function addChild(BlockInterface $child): self
         return new self(
             $this->metadata->updateHasChildren(true),
             $this->text,
+            $this->color,
             $children,
         );
     }
@@ -116,15 +122,27 @@ public function changeChildren(BlockInterface ...$children): self
         return new self(
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Paragraph.php b/src/Blocks/Paragraph.php
index 23260daa..901ed4f2 100644
--- a/src/Blocks/Paragraph.php
+++ b/src/Blocks/Paragraph.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Common\RichText;
 
 /**
@@ -12,6 +13,7 @@
  *      paragraph: array{
  *          rich_text: list<RichTextJson>,
  *          children?: list<BlockMetadataJson>,
+ *          color?: string,
  *      },
  * }
  *
@@ -27,6 +29,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly array $children,
+        public readonly Color $color,
     ) {
         $metadata->checkType(BlockType::Paragraph);
     }
@@ -35,7 +38,7 @@ public static function create(): self
     {
         $block = BlockMetadata::create(BlockType::Paragraph);
 
-        return new self($block, [], []);
+        return new self($block, [], [], Color::Default);
     }
 
     public static function fromString(string $content): self
@@ -43,7 +46,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Paragraph);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, []);
+        return new self($block, $text, [], Color::Default);
     }
 
     public static function fromArray(array $array): self
@@ -58,7 +61,9 @@ public static function fromArray(array $array): self
 
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $paragraph["children"] ?? []);
 
-        return new self($block, $text, $children);
+        $color = Color::tryFrom($paragraph["color"] ?? "") ?? Color::Default;
+
+        return new self($block, $text, $children, $color);
     }
 
     public function toArray(): array
@@ -68,6 +73,7 @@ public function toArray(): array
         $array["paragraph"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "children"  => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
+            "color"     => $this->color->value,
         ];
 
         return $array;
@@ -91,7 +97,7 @@ public function metadata(): BlockMetadata
     /** @param RichText[] $text */
     public function changeText(array $text): self
     {
-        return new self($this->metadata, $text, $this->children);
+        return new self($this->metadata, $text, $this->children, $this->color);
     }
 
     public function addText(RichText $text): self
@@ -99,7 +105,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->children);
+        return new self($this->metadata, $texts, $this->children, $this->color);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -110,6 +116,7 @@ public function changeChildren(BlockInterface ...$children): self
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
             $children,
+            $this->color,
         );
     }
 
@@ -122,6 +129,17 @@ public function addChild(BlockInterface $child): self
             $this->metadata->updateHasChildren(true),
             $this->text,
             $children,
+            $this->color,
+        );
+    }
+
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->children,
+            $color,
         );
     }
 
@@ -131,6 +149,7 @@ public function archive(): BlockInterface
             $this->metadata->archive(),
             $this->text,
             $this->children,
+            $this->color,
         );
     }
 }
diff --git a/src/Blocks/Quote.php b/src/Blocks/Quote.php
index 2e5f611c..22845e90 100644
--- a/src/Blocks/Quote.php
+++ b/src/Blocks/Quote.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\RichText;
 
@@ -12,6 +13,7 @@
  * @psalm-type QuoteJson = array{
  *      quote: array{
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children: list<BlockMetadataJson>,
  *      },
  * }
@@ -27,6 +29,7 @@ class Quote implements BlockInterface
     private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $metadata->checkType(BlockType::Quote);
@@ -36,7 +39,7 @@ public static function create(): self
     {
         $block = BlockMetadata::create(BlockType::Quote);
 
-        return new self($block, [], []);
+        return new self($block, [], Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -44,7 +47,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Quote);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, []);
+        return new self($block, $text, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -57,9 +60,11 @@ public static function fromArray(array $array): self
 
         $text = array_map(fn($t) => RichText::fromArray($t), $quote["rich_text"]);
 
+        $color = Color::tryFrom($quote["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $quote["children"] ?? []);
 
-        return new self($block, $text, $children);
+        return new self($block, $text, $color, $children);
     }
 
     public function toArray(): array
@@ -68,6 +73,7 @@ public function toArray(): array
 
         $array["quote"] = [
             "rich_text"     => array_map(fn(RichText $t) => $t->toArray(), $this->text),
+            "color"    => $this->color->value,
             "children" => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
@@ -92,7 +98,7 @@ public function metadata(): BlockMetadata
     /** @param RichText[] $text */
     public function changeText(array $text): self
     {
-        return new self($this->metadata, $text, $this->children);
+        return new self($this->metadata, $text, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -100,7 +106,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->children);
+        return new self($this->metadata, $texts, $this->color, $this->children);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -110,6 +116,7 @@ public function changeChildren(BlockInterface ...$children): self
         return new self(
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
+            $this->color,
             $children,
         );
     }
@@ -122,15 +129,27 @@ public function addChild(BlockInterface $child): self
         return new self(
             $this->metadata->updateHasChildren(true),
             $this->text,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/TableOfContents.php b/src/Blocks/TableOfContents.php
index 4cf400b6..4dcbb5e2 100644
--- a/src/Blocks/TableOfContents.php
+++ b/src/Blocks/TableOfContents.php
@@ -2,13 +2,16 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 
 /**
  * @psalm-import-type BlockMetadataJson from BlockMetadata
  *
  * @psalm-type TableOfContentsJson = array{
- *      table_of_contents: array<empty, empty>
+ *      table_of_contents: array{
+ *          color?: string
+ *      }
  * }
  *
  * @psalm-immutable
@@ -17,6 +20,7 @@ class TableOfContents implements BlockInterface
 {
     private function __construct(
         private readonly BlockMetadata $metadata,
+        public readonly Color $color,
     ) {
         $metadata->checkType(BlockType::TableOfContents);
     }
@@ -25,7 +29,7 @@ public static function create(): self
     {
         $block = BlockMetadata::create(BlockType::TableOfContents);
 
-        return new self($block);
+        return new self($block, Color::Default);
     }
 
     public static function fromArray(array $array): self
@@ -33,7 +37,12 @@ public static function fromArray(array $array): self
         /** @psalm-var BlockMetadataJson $array */
         $block = BlockMetadata::fromArray($array);
 
-        return new self($block);
+        /** @psalm-var TableOfContentsJson $array */
+        $toc = $array["table_of_contents"];
+
+        $color = Color::tryFrom($toc["color"] ?? "") ?? Color::Default;
+
+        return new self($block, $color);
     }
 
     public function toArray(): array
@@ -60,10 +69,19 @@ public function changeChildren(BlockInterface ...$children): never
         throw BlockException::noChindrenSupport();
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $color,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
+            $this->color,
         );
     }
 }
diff --git a/src/Blocks/ToDo.php b/src/Blocks/ToDo.php
index eefab22b..4a3dada8 100644
--- a/src/Blocks/ToDo.php
+++ b/src/Blocks/ToDo.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\RichText;
 
@@ -13,6 +14,7 @@
  *      to_do: array{
  *          checked: bool,
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children?: list<BlockMetadataJson>,
  *      },
  * }
@@ -29,6 +31,7 @@ private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
         public readonly bool $checked,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $metadata->checkType(BlockType::ToDo);
@@ -38,7 +41,7 @@ public static function create(): self
     {
         $block = BlockMetadata::create(BlockType::ToDo);
 
-        return new self($block, [], false, []);
+        return new self($block, [], false, Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -46,7 +49,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::ToDo);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, false, []);
+        return new self($block, $text, false, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -61,9 +64,11 @@ public static function fromArray(array $array): self
 
         $checked = $todo["checked"];
 
+        $color = Color::tryFrom($todo["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $todo["children"] ?? []);
 
-        return new self($block, $text, $checked, $children);
+        return new self($block, $text, $checked, $color, $children);
     }
 
     public function toArray(): array
@@ -73,6 +78,7 @@ public function toArray(): array
         $array["to_do"] = [
             "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
             "checked"   => $this->checked,
+            "color"     => $this->color->value,
             "children"  => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
@@ -96,7 +102,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->checked, $this->children);
+        return new self($this->metadata, $text, $this->checked, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -104,17 +110,17 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->checked, $this->children);
+        return new self($this->metadata, $texts, $this->checked, $this->color, $this->children);
     }
 
     public function check(): self
     {
-        return new self($this->metadata, $this->text, true, $this->children);
+        return new self($this->metadata, $this->text, true, $this->color, $this->children);
     }
 
     public function uncheck(): self
     {
-        return new self($this->metadata, $this->text, false, $this->children);
+        return new self($this->metadata, $this->text, false, $this->color, $this->children);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -125,6 +131,7 @@ public function changeChildren(BlockInterface ...$children): self
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
             $this->checked,
+            $this->color,
             $children,
         );
     }
@@ -138,16 +145,29 @@ public function addChild(BlockInterface $child): self
             $this->metadata->updateHasChildren(true),
             $this->text,
             $this->checked,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $this->checked,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
             $this->checked,
+            $this->color,
             $this->children,
         );
     }
diff --git a/src/Blocks/Toggle.php b/src/Blocks/Toggle.php
index 2bd3cccd..9a205ae0 100644
--- a/src/Blocks/Toggle.php
+++ b/src/Blocks/Toggle.php
@@ -2,6 +2,7 @@
 
 namespace Notion\Blocks;
 
+use Notion\Common\Color;
 use Notion\Common\RichText;
 
 /**
@@ -11,6 +12,7 @@
  * @psalm-type ToggleJson = array{
  *      toggle: array{
  *          rich_text: list<RichTextJson>,
+ *          color?: string,
  *          children?: list<BlockMetadataJson>,
  *      },
  * }
@@ -26,6 +28,7 @@ class Toggle implements BlockInterface
     private function __construct(
         private readonly BlockMetadata $metadata,
         public readonly array $text,
+        public readonly Color $color,
         public readonly array $children,
     ) {
         $metadata->checkType(BlockType::Toggle);
@@ -35,7 +38,7 @@ public static function createEmpty(): self
     {
         $block = BlockMetadata::create(BlockType::Toggle);
 
-        return new self($block, [], []);
+        return new self($block, [], Color::Default, []);
     }
 
     public static function fromString(string $content): self
@@ -43,7 +46,7 @@ public static function fromString(string $content): self
         $block = BlockMetadata::create(BlockType::Toggle);
         $text = [ RichText::fromString($content) ];
 
-        return new self($block, $text, []);
+        return new self($block, $text, Color::Default, []);
     }
 
     public static function fromArray(array $array): self
@@ -56,9 +59,11 @@ public static function fromArray(array $array): self
 
         $text = array_map(fn($t) => RichText::fromArray($t), $toggle["rich_text"]);
 
+        $color = Color::tryFrom($toggle["color"] ?? "") ?? Color::Default;
+
         $children = array_map(fn($b) => BlockFactory::fromArray($b), $toggle["children"] ?? []);
 
-        return new self($block, $text, $children);
+        return new self($block, $text, $color, $children);
     }
 
     public function toArray(): array
@@ -66,8 +71,9 @@ public function toArray(): array
         $array = $this->metadata->toArray();
 
         $array["toggle"] = [
-            "rich_text"     => array_map(fn(RichText $t) => $t->toArray(), $this->text),
-            "children" => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
+            "rich_text" => array_map(fn(RichText $t) => $t->toArray(), $this->text),
+            "color"     => $this->color->value,
+            "children"  => array_map(fn(BlockInterface $b) => $b->toArray(), $this->children),
         ];
 
         return $array;
@@ -90,7 +96,7 @@ public function metadata(): BlockMetadata
 
     public function changeText(RichText ...$text): self
     {
-        return new self($this->metadata, $text, $this->children);
+        return new self($this->metadata, $text, $this->color, $this->children);
     }
 
     public function addText(RichText $text): self
@@ -98,7 +104,7 @@ public function addText(RichText $text): self
         $texts = $this->text;
         $texts[] = $text;
 
-        return new self($this->metadata, $texts, $this->children);
+        return new self($this->metadata, $texts, $this->color, $this->children);
     }
 
     public function changeChildren(BlockInterface ...$children): self
@@ -108,6 +114,7 @@ public function changeChildren(BlockInterface ...$children): self
         return new self(
             $this->metadata->updateHasChildren($hasChildren),
             $this->text,
+            $this->color,
             $children,
         );
     }
@@ -120,15 +127,27 @@ public function addChild(BlockInterface $child): self
         return new self(
             $this->metadata->updateHasChildren(true),
             $this->text,
+            $this->color,
             $children,
         );
     }
 
+    public function changeColor(Color $color): self
+    {
+        return new self(
+            $this->metadata->update(),
+            $this->text,
+            $color,
+            $this->children,
+        );
+    }
+
     public function archive(): BlockInterface
     {
         return new self(
             $this->metadata->archive(),
             $this->text,
+            $this->color,
             $this->children,
         );
     }
diff --git a/tests/Unit/Blocks/BulletedListItemTest.php b/tests/Unit/Blocks/BulletedListItemTest.php
index e114bed5..4391d95f 100644
--- a/tests/Unit/Blocks/BulletedListItemTest.php
+++ b/tests/Unit/Blocks/BulletedListItemTest.php
@@ -4,6 +4,7 @@
 
 use Notion\Blocks\BlockFactory;
 use Notion\Blocks\BulletedListItem;
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\Date;
 use Notion\Common\RichText;
@@ -133,6 +134,7 @@ public function test_transform_in_array(): void
                         "color"         => "default",
                     ],
                 ]],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -185,4 +187,11 @@ public function test_add_child(): void
         $this->assertCount(1, $item->children);
         $this->assertEquals($nested, $item->children[0]);
     }
+
+    public function test_change_color(): void
+    {
+        $block = BulletedListItem::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/CalloutTest.php b/tests/Unit/Blocks/CalloutTest.php
index 71ff6dcb..0450aa11 100644
--- a/tests/Unit/Blocks/CalloutTest.php
+++ b/tests/Unit/Blocks/CalloutTest.php
@@ -4,6 +4,7 @@
 
 use Notion\Blocks\BlockFactory;
 use Notion\Blocks\Callout;
+use Notion\Common\Color;
 use Notion\Exceptions\BlockException;
 use Notion\Common\Date;
 use Notion\Common\Emoji;
@@ -235,6 +236,7 @@ public function test_transform_in_array(): void
                     "type"  => "emoji",
                     "emoji" => "☀️",
                 ],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -307,4 +309,11 @@ public function test_replace_icon_file(): void
 
         $this->assertTrue($callout->icon->isFile());
     }
+
+    public function test_change_color(): void
+    {
+        $block = Callout::fromString("☀️", "Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/Heading1Test.php b/tests/Unit/Blocks/Heading1Test.php
index 905ae20d..94dccbc5 100644
--- a/tests/Unit/Blocks/Heading1Test.php
+++ b/tests/Unit/Blocks/Heading1Test.php
@@ -6,6 +6,7 @@
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Heading1;
 use Notion\Blocks\Paragraph;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -74,6 +75,7 @@ public function test_create_from_array(): void
                 ],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -137,6 +139,7 @@ public function test_transform_in_array(): void
                 ]],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -279,6 +282,7 @@ public function test_toggleable_array_conversion(): void
                         "divider"          => new \stdClass(),
                     ]
                 ],
+                "color" => "default",
             ],
         ];
 
@@ -286,4 +290,11 @@ public function test_toggleable_array_conversion(): void
 
         $this->assertEquals($array, $heading->toArray());
     }
+
+    public function test_change_color(): void
+    {
+        $h1 = Heading1::fromString("Hello!")->changeColor(Color::Green);
+
+        $this->assertSame(Color::Green, $h1->color);
+    }
 }
diff --git a/tests/Unit/Blocks/Heading2Test.php b/tests/Unit/Blocks/Heading2Test.php
index 7780c4e4..7b0a25db 100644
--- a/tests/Unit/Blocks/Heading2Test.php
+++ b/tests/Unit/Blocks/Heading2Test.php
@@ -6,6 +6,7 @@
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Heading2;
 use Notion\Blocks\Paragraph;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -74,6 +75,7 @@ public function test_create_from_array(): void
                 ],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -100,7 +102,7 @@ public function test_error_on_wrong_type(): void
             "type"             => "wrong-type",
             "heading_2"        => [
                 "rich_text"     => [],
-                "is_toggleable" => true,
+                "is_toggleable"  => false,
             ],
         ];
 
@@ -137,6 +139,7 @@ public function test_transform_in_array(): void
                 ]],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -279,6 +282,7 @@ public function test_toggleable_array_conversion(): void
                         "divider"          => new \stdClass(),
                     ]
                 ],
+                "color" => "default",
             ],
         ];
 
@@ -286,4 +290,11 @@ public function test_toggleable_array_conversion(): void
 
         $this->assertEquals($array, $heading->toArray());
     }
+
+    public function test_change_color(): void
+    {
+        $h1 = Heading2::fromString("Hello!")->changeColor(Color::Green);
+
+        $this->assertSame(Color::Green, $h1->color);
+    }
 }
diff --git a/tests/Unit/Blocks/Heading3Test.php b/tests/Unit/Blocks/Heading3Test.php
index 0a132ae8..51d38bc8 100644
--- a/tests/Unit/Blocks/Heading3Test.php
+++ b/tests/Unit/Blocks/Heading3Test.php
@@ -6,6 +6,7 @@
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Heading3;
 use Notion\Blocks\Paragraph;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use Notion\Exceptions\HeadingException;
@@ -74,6 +75,7 @@ public function test_create_from_array(): void
                 ],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -100,7 +102,7 @@ public function test_error_on_wrong_type(): void
             "type"             => "wrong-type",
             "heading_3"        => [
                 "rich_text"     => [],
-                "is_toggleable" => false,
+                "is_toggleable"  => false,
             ],
         ];
 
@@ -137,6 +139,7 @@ public function test_transform_in_array(): void
                 ]],
                 "is_toggleable" => false,
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -279,6 +282,7 @@ public function test_toggleable_array_conversion(): void
                         "divider"          => new \stdClass(),
                     ]
                 ],
+                "color" => "default",
             ],
         ];
 
@@ -286,4 +290,11 @@ public function test_toggleable_array_conversion(): void
 
         $this->assertEquals($array, $heading->toArray());
     }
+
+    public function test_change_color(): void
+    {
+        $h1 = Heading3::fromString("Hello!")->changeColor(Color::Green);
+
+        $this->assertSame(Color::Green, $h1->color);
+    }
 }
diff --git a/tests/Unit/Blocks/NumberedListItemTest.php b/tests/Unit/Blocks/NumberedListItemTest.php
index 1bf6bc79..37668188 100644
--- a/tests/Unit/Blocks/NumberedListItemTest.php
+++ b/tests/Unit/Blocks/NumberedListItemTest.php
@@ -5,6 +5,7 @@
 use Notion\Blocks\BlockFactory;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\NumberedListItem;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use PHPUnit\Framework\TestCase;
@@ -133,6 +134,7 @@ public function test_transform_in_array(): void
                         "color"         => "default",
                     ],
                 ]],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -185,4 +187,11 @@ public function test_add_child(): void
         $this->assertCount(1, $item->children);
         $this->assertEquals($nested, $item->children[0]);
     }
+
+    public function test_change_color(): void
+    {
+        $block = NumberedListItem::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/ParagraphTest.php b/tests/Unit/Blocks/ParagraphTest.php
index 781a1b06..8e198b46 100644
--- a/tests/Unit/Blocks/ParagraphTest.php
+++ b/tests/Unit/Blocks/ParagraphTest.php
@@ -5,6 +5,7 @@
 use Notion\Blocks\BlockFactory;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Paragraph;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use PHPUnit\Framework\TestCase;
@@ -72,6 +73,7 @@ public function test_create_from_array(): void
                     ],
                 ],
                 "children" => [],
+                "color" => "green",
             ],
         ];
 
@@ -133,6 +135,7 @@ public function test_transform_in_array(): void
                     ],
                 ]],
                 "children" => [],
+                "color" => "default",
             ],
         ];
 
@@ -184,4 +187,11 @@ public function test_add_child(): void
         $this->assertCount(1, $paragraph->children);
         $this->assertEquals($nested, $paragraph->children[0]);
     }
+
+    public function test_change_color(): void
+    {
+        $paragraph = Paragraph::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $paragraph->color);
+    }
 }
diff --git a/tests/Unit/Blocks/QuoteTest.php b/tests/Unit/Blocks/QuoteTest.php
index b09273c8..3da23cf3 100644
--- a/tests/Unit/Blocks/QuoteTest.php
+++ b/tests/Unit/Blocks/QuoteTest.php
@@ -5,6 +5,7 @@
 use Notion\Blocks\BlockFactory;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Quote;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use PHPUnit\Framework\TestCase;
@@ -133,6 +134,7 @@ public function test_transform_in_array(): void
                         "color"         => "default",
                     ],
                 ]],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -193,4 +195,11 @@ public function test_archive(): void
 
         $this->assertTrue($quote->metadata()->archived);
     }
+
+    public function test_change_color(): void
+    {
+        $block = Quote::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/TableOfContentsTest.php b/tests/Unit/Blocks/TableOfContentsTest.php
index 96a47637..1543e184 100644
--- a/tests/Unit/Blocks/TableOfContentsTest.php
+++ b/tests/Unit/Blocks/TableOfContentsTest.php
@@ -6,6 +6,7 @@
 use Notion\Blocks\Paragraph;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\TableOfContents;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use PHPUnit\Framework\TestCase;
 
@@ -28,7 +29,9 @@ public function test_create_from_array(): void
             "archived"         => false,
             "has_children"     => false,
             "type"             => "table_of_contents",
-            "table_of_contents" => new \stdClass(),
+            "table_of_contents" => [
+                "color" => "green",
+            ]
         ];
 
         $tableOfContents = TableOfContents::fromArray($array);
@@ -47,7 +50,7 @@ public function test_error_on_wrong_type(): void
             "archived"         => false,
             "has_children"     => false,
             "type"             => "wrong-type",
-            "table_of_contents" => new \stdClass(),
+            "table_of_contents" => []
         ];
 
         TableOfContents::fromArray($array);
@@ -87,4 +90,11 @@ public function test_no_children_support_2(): void
         /** @psalm-suppress UnusedMethodCall */
         $block->addChild(Paragraph::create());
     }
+
+    public function test_change_color(): void
+    {
+        $block = TableOfContents::create()->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/ToDoTest.php b/tests/Unit/Blocks/ToDoTest.php
index ec404ca1..8dc6e536 100644
--- a/tests/Unit/Blocks/ToDoTest.php
+++ b/tests/Unit/Blocks/ToDoTest.php
@@ -5,6 +5,7 @@
 use Notion\Blocks\BlockFactory;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\ToDo;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use PHPUnit\Framework\TestCase;
@@ -138,6 +139,7 @@ public function test_transform_in_array(): void
                         "color"         => "default",
                     ],
                 ]],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -205,4 +207,11 @@ public function test_uncheck_item(): void
 
         $this->assertFalse($toDo->checked);
     }
+
+    public function test_change_color(): void
+    {
+        $block = ToDo::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }
diff --git a/tests/Unit/Blocks/ToggleTest.php b/tests/Unit/Blocks/ToggleTest.php
index 811b6ab2..71fa28eb 100644
--- a/tests/Unit/Blocks/ToggleTest.php
+++ b/tests/Unit/Blocks/ToggleTest.php
@@ -3,8 +3,10 @@
 namespace Notion\Test\Unit\Blocks;
 
 use Notion\Blocks\BlockFactory;
+use Notion\Blocks\ToDo;
 use Notion\Exceptions\BlockException;
 use Notion\Blocks\Toggle;
+use Notion\Common\Color;
 use Notion\Common\Date;
 use Notion\Common\RichText;
 use PHPUnit\Framework\TestCase;
@@ -132,6 +134,7 @@ public function test_transform_in_array(): void
                         "color"         => "default",
                     ],
                 ]],
+                "color" => "default",
                 "children" => [],
             ],
         ];
@@ -184,4 +187,11 @@ public function test_add_child(): void
         $this->assertCount(1, $toggle->children);
         $this->assertEquals($nestedToggle, $toggle->children[0]);
     }
+
+    public function test_change_color(): void
+    {
+        $block = ToDo::fromString("Hello World!")->changeColor(Color::Red);
+
+        $this->assertSame(Color::Red, $block->color);
+    }
 }