diff --git a/modules/multiplayer/tests/test_multiplayer_spawner.h b/modules/multiplayer/tests/test_multiplayer_spawner.h
new file mode 100644
index 000000000000..2efe38452d18
--- /dev/null
+++ b/modules/multiplayer/tests/test_multiplayer_spawner.h
@@ -0,0 +1,448 @@
+/**************************************************************************/
+/*  test_multiplayer_spawner.h                                            */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#ifndef TEST_MULTIPLAYER_SPAWNER_H
+#define TEST_MULTIPLAYER_SPAWNER_H
+
+#include "tests/test_macros.h"
+#include "tests/test_utils.h"
+
+#include "../multiplayer_spawner.h"
+
+namespace TestMultiplayerSpawner {
+
+static inline Array build_array() {
+	return Array();
+}
+template <typename... Targs>
+static inline Array build_array(Variant item, Targs... Fargs) {
+	Array a = build_array(Fargs...);
+	a.push_front(item);
+	return a;
+}
+
+class Wasp : public Node {
+	GDCLASS(Wasp, Node);
+
+	int _size = 0;
+
+public:
+	int get_size() const {
+		return _size;
+	}
+	void set_size(int p_size) {
+		_size = p_size;
+	}
+
+	Wasp() {
+		set_name("Wasp");
+		set_scene_file_path("wasp.tscn");
+	}
+};
+
+class SpawnWasps : public Object {
+	GDCLASS(SpawnWasps, Object);
+
+protected:
+	static void _bind_methods() {
+		ClassDB::bind_method(D_METHOD("wasp", "size"), &SpawnWasps::create_wasps);
+		{
+			MethodInfo mi;
+			mi.name = "wasp_error";
+			mi.arguments.push_back(PropertyInfo(Variant::INT, "size"));
+
+			ClassDB::bind_vararg_method(METHOD_FLAGS_DEFAULT, "wasp_error", &SpawnWasps::create_wasps_error, mi, varray(), false);
+		}
+		ClassDB::bind_method(D_METHOD("echo", "size"), &SpawnWasps::echo_size);
+	}
+
+public:
+	Wasp *create_wasps(int p_size) {
+		Wasp *wasp = memnew(Wasp);
+		wasp->set_size(p_size);
+		return wasp;
+	}
+
+	Wasp *create_wasps_error(const Variant **p_args, int p_argcount, Callable::CallError &r_error) {
+		r_error.error = Callable::CallError::CALL_ERROR_INVALID_ARGUMENT;
+		return nullptr;
+	}
+
+	int echo_size(int p_size) {
+		return p_size;
+	}
+};
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner] Defaults") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+
+	CHECK_EQ(multiplayer_spawner->get_configuration_warnings().size(), 1);
+	CHECK_EQ(multiplayer_spawner->get_spawn_node(), nullptr);
+	CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 0);
+	CHECK_EQ(multiplayer_spawner->get_spawn_path(), NodePath());
+	CHECK_EQ(multiplayer_spawner->get_spawn_limit(), 0);
+	CHECK_EQ(multiplayer_spawner->get_spawn_function(), Callable());
+
+	memdelete(multiplayer_spawner);
+}
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner][SceneTree] Spawn Path warning") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+	SceneTree::get_singleton()->get_root()->add_child(multiplayer_spawner);
+
+	// If there is no spawn path, there should be a warning.
+	PackedStringArray warning_messages = multiplayer_spawner->get_configuration_warnings();
+	REQUIRE_EQ(warning_messages.size(), 1);
+	CHECK_MESSAGE(warning_messages[0].contains("\"Spawn Path\""), "Invalid configuration warning");
+
+	// If there is a spawn path, but it doesn't exist a node on it, there should be a warning.
+	multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+	warning_messages = multiplayer_spawner->get_configuration_warnings();
+	REQUIRE_EQ(warning_messages.size(), 1);
+	CHECK_MESSAGE(warning_messages[0].contains("\"Spawn Path\""), "Invalid configuration warning");
+
+	// If there is a spawn path and a node on it, shouldn't be a warning.
+	Node *foo = memnew(Node);
+	foo->set_name("Foo");
+	SceneTree::get_singleton()->get_root()->add_child(foo);
+	warning_messages = multiplayer_spawner->get_configuration_warnings();
+	CHECK_EQ(warning_messages.size(), 0);
+
+	memdelete(foo);
+	memdelete(multiplayer_spawner);
+}
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner][SceneTree] Spawn node") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+	SceneTree::get_singleton()->get_root()->add_child(multiplayer_spawner);
+	CHECK_EQ(multiplayer_spawner->get_spawn_node(), nullptr);
+
+	Node *foo = memnew(Node);
+	foo->set_name("Foo");
+	SceneTree::get_singleton()->get_root()->add_child(foo);
+
+	SUBCASE("nullptr if spawn path doesn't exists") {
+		multiplayer_spawner->set_spawn_path(NodePath("/root/NotExists"));
+
+		CHECK_EQ(multiplayer_spawner->get_spawn_node(), nullptr);
+	}
+
+	SUBCASE("Get it after setting spawn path with no signal connections") {
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+
+		CHECK_EQ(multiplayer_spawner->get_spawn_node(), foo);
+		CHECK_FALSE(foo->has_connections("child_entered_tree"));
+	}
+
+	SUBCASE("Get it after setting spawn path with signal connections") {
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+
+		CHECK_EQ(multiplayer_spawner->get_spawn_node(), foo);
+		CHECK(foo->has_connections("child_entered_tree"));
+	}
+
+	SUBCASE("Set a new one should disconnect signals from the old one") {
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+
+		CHECK_EQ(multiplayer_spawner->get_spawn_node(), foo);
+		CHECK(foo->has_connections("child_entered_tree"));
+
+		Node *bar = memnew(Node);
+		bar->set_name("Bar");
+		SceneTree::get_singleton()->get_root()->add_child(bar);
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Bar"));
+
+		CHECK_EQ(multiplayer_spawner->get_spawn_node(), bar);
+		CHECK(bar->has_connections("child_entered_tree"));
+		CHECK_FALSE(foo->has_connections("child_entered_tree"));
+
+		memdelete(bar);
+	}
+
+	memdelete(foo);
+	memdelete(multiplayer_spawner);
+}
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner][SceneTree] Spawnable scene") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+	SceneTree::get_singleton()->get_root()->add_child(multiplayer_spawner);
+	CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 0);
+
+	SUBCASE("Add one") {
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 1);
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene(0), "scene.tscn");
+	}
+
+	SUBCASE("Add one and if there is a valid spawn path add a connection to it") {
+		Node *foo = memnew(Node);
+		foo->set_name("Foo");
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+		CHECK_FALSE(foo->has_connections("child_entered_tree"));
+
+		// Adding now foo to the tree to avoid set_spawn_path() making the connection.
+		SceneTree::get_singleton()->get_root()->add_child(foo);
+		multiplayer_spawner->notification(Node::NOTIFICATION_POST_ENTER_TREE);
+		CHECK_FALSE(foo->has_connections("child_entered_tree"));
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+		CHECK(foo->has_connections("child_entered_tree"));
+
+		memdelete(foo);
+	}
+
+	SUBCASE("Add multiple") {
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+		multiplayer_spawner->add_spawnable_scene("other_scene.tscn");
+		multiplayer_spawner->add_spawnable_scene("yet_another_scene.tscn");
+
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 3);
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene(0), "scene.tscn");
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene(1), "other_scene.tscn");
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene(2), "yet_another_scene.tscn");
+	}
+
+	SUBCASE("Clear") {
+		Node *foo = memnew(Node);
+		foo->set_name("Foo");
+		SceneTree::get_singleton()->get_root()->add_child(foo);
+		multiplayer_spawner->set_spawn_path(NodePath("/root/Foo"));
+
+		multiplayer_spawner->add_spawnable_scene("scene.tscn");
+		multiplayer_spawner->add_spawnable_scene("other_scene.tscn");
+		multiplayer_spawner->add_spawnable_scene("yet_another_scene.tscn");
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 3);
+		CHECK(foo->has_connections("child_entered_tree"));
+
+		multiplayer_spawner->clear_spawnable_scenes();
+
+		CHECK_EQ(multiplayer_spawner->get_spawnable_scene_count(), 0);
+		CHECK_FALSE(foo->has_connections("child_entered_tree"));
+	}
+
+	memdelete(multiplayer_spawner);
+}
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner][SceneTree] Instantiate custom") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+	SceneTree::get_singleton()->get_root()->add_child(multiplayer_spawner);
+	CHECK_EQ(multiplayer_spawner->get_spawn_node(), nullptr);
+
+	Node *nest = memnew(Node);
+	nest->set_name("Nest");
+	SceneTree::get_singleton()->get_root()->add_child(nest);
+	multiplayer_spawner->set_spawn_path(NodePath("/root/Nest"));
+
+	SpawnWasps *spawn_wasps = memnew(SpawnWasps);
+
+	SUBCASE("Instantiates a node properly") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+		Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->instantiate_custom(Variant(42)));
+		CHECK_NE(wasp, nullptr);
+		CHECK_EQ(wasp->get_name(), "Wasp");
+		CHECK_EQ(wasp->get_size(), 42);
+
+		memdelete(wasp);
+	}
+
+	SUBCASE("Instantiates multiple nodes properly if there is no spawn limit") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+
+		for (int i = 0; i < 10; i++) {
+			Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->instantiate_custom(Variant(i)));
+			CHECK_NE(wasp, nullptr);
+			CHECK_EQ(wasp->get_name(), "Wasp");
+			CHECK_EQ(wasp->get_size(), i);
+			nest->add_child(wasp, true);
+		}
+	}
+
+	SUBCASE("Fails if spawn limit is reached") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+
+		// This one works.
+		Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->instantiate_custom(Variant(42)));
+		CHECK_NE(wasp, nullptr);
+		CHECK_EQ(wasp->get_name(), "Wasp");
+		CHECK_EQ(wasp->get_size(), 42);
+		// Adding to the spawner node to get it tracked.
+		nest->add_child(wasp);
+
+		// This one fails because spawn limit is reached.
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->instantiate_custom(Variant(255)), nullptr);
+		ERR_PRINT_ON;
+
+		memdelete(wasp);
+	}
+
+	SUBCASE("Fails if spawn function is not set") {
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->instantiate_custom(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when spawn function fails") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp_error"));
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->instantiate_custom(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when spawn function not returns a node") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "echo"));
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->instantiate_custom(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	memdelete(spawn_wasps);
+	memdelete(nest);
+	memdelete(multiplayer_spawner);
+}
+
+TEST_CASE("[Multiplayer][MultiplayerSpawner][SceneTree] Spawn") {
+	MultiplayerSpawner *multiplayer_spawner = memnew(MultiplayerSpawner);
+
+	SUBCASE("Fails because is not inside tree") {
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->spawn(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	SceneTree::get_singleton()->get_root()->add_child(multiplayer_spawner);
+	CHECK_EQ(multiplayer_spawner->get_spawn_node(), nullptr);
+
+	Node *nest = memnew(Node);
+	nest->set_name("Nest");
+	SceneTree::get_singleton()->get_root()->add_child(nest);
+	multiplayer_spawner->set_spawn_path(NodePath("/root/Nest"));
+
+	SpawnWasps *spawn_wasps = memnew(SpawnWasps);
+	multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+	SUBCASE("Spawns a node, track it and add it to spawn node") {
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+		Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->spawn(Variant(42)));
+		CHECK_NE(wasp, nullptr);
+		CHECK_EQ(wasp->get_name(), "Wasp");
+		CHECK_EQ(wasp->get_size(), 42);
+		CHECK_EQ(wasp->get_parent(), nest);
+		CHECK_EQ(nest->get_child_count(), 1);
+		CHECK_EQ(nest->get_child(0), wasp);
+	}
+
+	SUBCASE("Spawns multiple nodes properly if there is no spawn limit") {
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+
+		for (int i = 0; i < 10; i++) {
+			Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->spawn(Variant(i)));
+			CHECK_NE(wasp, nullptr);
+			CHECK_EQ(wasp->get_name(), "Wasp" + String((i == 0) ? "" : itos(i + 1)));
+			CHECK_EQ(wasp->get_size(), i);
+			CHECK_EQ(wasp->get_parent(), nest);
+			CHECK_EQ(nest->get_child_count(), i + 1);
+			CHECK_EQ(nest->get_child(i), wasp);
+		}
+	}
+
+	SUBCASE("Fails if spawn limit is reached") {
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+
+		// This one works.
+		Wasp *wasp = Object::cast_to<Wasp>(multiplayer_spawner->spawn(Variant(42)));
+		CHECK_NE(wasp, nullptr);
+		CHECK_EQ(wasp->get_name(), "Wasp");
+		CHECK_EQ(wasp->get_size(), 42);
+		CHECK_EQ(wasp->get_parent(), nest);
+		CHECK_EQ(nest->get_child_count(), 1);
+		CHECK_EQ(nest->get_child(0), wasp);
+
+		// This one fails because spawn limit is reached.
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->spawn(Variant(255)), nullptr);
+		ERR_PRINT_ON;
+
+		memdelete(wasp);
+	}
+
+	SUBCASE("Fails if spawn function is not set") {
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->spawn(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails if spawn node cannot be found") {
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "wasp"));
+		multiplayer_spawner->set_spawn_path(NodePath(""));
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->spawn(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	SUBCASE("Fails when instantiate_custom not returns a node") {
+		multiplayer_spawner->add_spawnable_scene("wasp.tscn");
+
+		multiplayer_spawner->set_spawn_limit(1);
+		multiplayer_spawner->set_spawn_function(Callable(spawn_wasps, "echo"));
+
+		ERR_PRINT_OFF;
+		CHECK_EQ(multiplayer_spawner->spawn(Variant(42)), nullptr);
+		ERR_PRINT_ON;
+	}
+
+	memdelete(spawn_wasps);
+	memdelete(nest);
+	memdelete(multiplayer_spawner);
+}
+
+} // namespace TestMultiplayerSpawner
+
+#endif // TEST_MULTIPLAYER_SPAWNER_H