diff --git a/src/creatures/combat/condition.cpp b/src/creatures/combat/condition.cpp
index da90b03f65a..eac70f8ba74 100644
--- a/src/creatures/combat/condition.cpp
+++ b/src/creatures/combat/condition.cpp
@@ -1769,6 +1769,10 @@ bool ConditionDamage::getNextDamage(int32_t &damage) {
 }
 
 bool ConditionDamage::doDamage(const std::shared_ptr<Creature> &creature, int32_t healthChange) const {
+	if (owner == 0) {
+		return false;
+	}
+
 	const auto &attacker = g_game().getPlayerByGUID(owner) ? g_game().getPlayerByGUID(owner)->getCreature() : g_game().getCreatureByID(owner);
 	bool isPlayer = attacker && attacker->getPlayer();
 	if (creature->isSuppress(getType(), isPlayer)) {
diff --git a/src/creatures/monsters/monster.cpp b/src/creatures/monsters/monster.cpp
index 13b30321a21..845544d61e9 100644
--- a/src/creatures/monsters/monster.cpp
+++ b/src/creatures/monsters/monster.cpp
@@ -35,6 +35,7 @@ std::shared_ptr<Monster> Monster::createMonster(const std::string &name) {
 }
 
 Monster::Monster(const std::shared_ptr<MonsterType> &mType) :
+	m_lowerName(asLowerCaseString(mType->name)),
 	nameDescription(asLowerCaseString(mType->nameDescription)),
 	mType(mType) {
 	defaultOutfit = mType->info.outfit;
diff --git a/src/creatures/monsters/monster.hpp b/src/creatures/monsters/monster.hpp
index 6e44d8f36bf..3661eea9bef 100644
--- a/src/creatures/monsters/monster.hpp
+++ b/src/creatures/monsters/monster.hpp
@@ -49,6 +49,10 @@ class Monster final : public Creature {
 	void setNameDescription(std::string_view nameDescription);
 	std::string getDescription(int32_t) override;
 
+	const std::string &getLowerName() const {
+		return m_lowerName;
+	}
+
 	CreatureType_t getType() const override;
 
 	const Position &getMasterPos() const;
@@ -244,6 +248,7 @@ class Monster final : public Creature {
 	ForgeClassifications_t monsterForgeClassification = ForgeClassifications_t::FORGE_NORMAL_MONSTER;
 
 	std::string name;
+	std::string m_lowerName;
 	std::string nameDescription;
 
 	std::shared_ptr<MonsterType> mType;
diff --git a/src/creatures/npcs/npc.cpp b/src/creatures/npcs/npc.cpp
index 5ce48cbbb7b..65bec559872 100644
--- a/src/creatures/npcs/npc.cpp
+++ b/src/creatures/npcs/npc.cpp
@@ -97,6 +97,10 @@ void Npc::setName(std::string newName) const {
 	npcType->name = std::move(newName);
 }
 
+const std::string &Npc::getLowerName() const {
+	return npcType->m_lowerName;
+}
+
 CreatureType_t Npc::getType() const {
 	return CREATURETYPE_NPC;
 }
diff --git a/src/creatures/npcs/npc.hpp b/src/creatures/npcs/npc.hpp
index dc3e16961f1..47945b79e99 100644
--- a/src/creatures/npcs/npc.hpp
+++ b/src/creatures/npcs/npc.hpp
@@ -51,6 +51,8 @@ class Npc final : public Creature {
 
 	void setName(std::string newName) const;
 
+	const std::string &getLowerName() const;
+
 	CreatureType_t getType() const override;
 
 	const Position &getMasterPos() const;
diff --git a/src/creatures/npcs/npcs.cpp b/src/creatures/npcs/npcs.cpp
index 53ed757336f..9abc6be6efd 100644
--- a/src/creatures/npcs/npcs.cpp
+++ b/src/creatures/npcs/npcs.cpp
@@ -16,6 +16,9 @@
 #include "lua/scripts/scripts.hpp"
 #include "lib/di/container.hpp"
 
+NpcType::NpcType(const std::string &initName) :
+	name(initName), m_lowerName(asLowerCaseString(initName)), typeName(initName), nameDescription(initName) {};
+
 bool NpcType::canSpawn(const Position &pos) const {
 	bool canSpawn = true;
 	const bool isDay = g_game().gameIsDay();
diff --git a/src/creatures/npcs/npcs.hpp b/src/creatures/npcs/npcs.hpp
index b91e1547c07..d587a17b9fa 100644
--- a/src/creatures/npcs/npcs.hpp
+++ b/src/creatures/npcs/npcs.hpp
@@ -77,14 +77,14 @@ class NpcType final : public SharedObject {
 
 public:
 	NpcType() = default;
-	explicit NpcType(const std::string &initName) :
-		name(initName), typeName(initName), nameDescription(initName) {};
+	explicit NpcType(const std::string &initName);
 
 	// non-copyable
 	NpcType(const NpcType &) = delete;
 	NpcType &operator=(const NpcType &) = delete;
 
 	std::string name;
+	std::string m_lowerName;
 	std::string typeName;
 	std::string nameDescription;
 	NpcInfo info;
diff --git a/src/game/game.cpp b/src/game/game.cpp
index 7da1d87fb4a..54a666337d3 100644
--- a/src/game/game.cpp
+++ b/src/game/game.cpp
@@ -424,7 +424,7 @@ Game &Game::getInstance() {
 }
 
 void Game::resetMonsters() const {
-	for (const auto &[monsterId, monster] : getMonsters()) {
+	for (const auto &monster : getMonsters()) {
 		monster->clearTargetList();
 		monster->clearFriendList();
 	}
@@ -432,7 +432,7 @@ void Game::resetMonsters() const {
 
 void Game::resetNpcs() const {
 	// Close shop window from all npcs and reset the shopPlayerSet
-	for (const auto &[npcId, npc] : getNpcs()) {
+	for (const auto &npc : getNpcs()) {
 		npc->closeAllShopWindows();
 		npc->resetPlayerInteractions();
 	}
@@ -954,11 +954,16 @@ std::shared_ptr<Monster> Game::getMonsterByID(uint32_t id) {
 		return nullptr;
 	}
 
-	auto it = monsters.find(id);
-	if (it == monsters.end()) {
+	auto it = monstersIdIndex.find(id);
+	if (it == monstersIdIndex.end()) {
 		return nullptr;
 	}
-	return it->second;
+
+	if (it->second >= monsters.size()) {
+		return nullptr;
+	}
+
+	return monsters[it->second];
 }
 
 std::shared_ptr<Npc> Game::getNpcByID(uint32_t id) {
@@ -966,11 +971,12 @@ std::shared_ptr<Npc> Game::getNpcByID(uint32_t id) {
 		return nullptr;
 	}
 
-	auto it = npcs.find(id);
-	if (it == npcs.end()) {
+	auto it = npcsIdIndex.find(id);
+	if (it == npcsIdIndex.end()) {
 		return nullptr;
 	}
-	return it->second;
+
+	return npcs[it->second];
 }
 
 std::shared_ptr<Player> Game::getPlayerByID(uint32_t id, bool allowOffline /* = false */) {
@@ -990,43 +996,41 @@ std::shared_ptr<Player> Game::getPlayerByID(uint32_t id, bool allowOffline /* =
 	return tmpPlayer;
 }
 
-std::shared_ptr<Creature> Game::getCreatureByName(const std::string &s) {
-	if (s.empty()) {
+std::shared_ptr<Creature> Game::getCreatureByName(const std::string &creatureName) {
+	if (creatureName.empty()) {
 		return nullptr;
 	}
 
-	const std::string &lowerCaseName = asLowerCaseString(s);
+	const std::string &lowerCaseName = asLowerCaseString(creatureName);
 
 	auto m_it = mappedPlayerNames.find(lowerCaseName);
 	if (m_it != mappedPlayerNames.end()) {
 		return m_it->second.lock();
 	}
 
-	for (const auto &it : npcs) {
-		if (lowerCaseName == asLowerCaseString(it.second->getName())) {
-			return it.second;
-		}
+	auto npcIterator = npcsNameIndex.find(lowerCaseName);
+	if (npcIterator != npcsNameIndex.end()) {
+		return npcs[npcIterator->second];
 	}
 
-	for (const auto &it : monsters) {
-		if (lowerCaseName == asLowerCaseString(it.second->getName())) {
-			return it.second;
-		}
+	auto monsterIterator = monstersNameIndex.find(lowerCaseName);
+	if (monsterIterator != monstersNameIndex.end()) {
+		return monsters[monsterIterator->second];
 	}
 	return nullptr;
 }
 
-std::shared_ptr<Npc> Game::getNpcByName(const std::string &s) {
-	if (s.empty()) {
+std::shared_ptr<Npc> Game::getNpcByName(const std::string &npcName) {
+	if (npcName.empty()) {
 		return nullptr;
 	}
 
-	const char* npcName = s.c_str();
-	for (const auto &it : npcs) {
-		if (strcasecmp(npcName, it.second->getName().c_str()) == 0) {
-			return it.second;
-		}
+	const std::string lowerCaseName = asLowerCaseString(npcName);
+	auto it = npcsNameIndex.find(lowerCaseName);
+	if (it != npcsNameIndex.end()) {
+		return npcs[it->second];
 	}
+
 	return nullptr;
 }
 
@@ -3184,13 +3188,18 @@ ReturnValue Game::internalCollectManagedItems(const std::shared_ptr<Player> &pla
 
 ReturnValue Game::collectRewardChestItems(const std::shared_ptr<Player> &player, uint32_t maxMoveItems /* = 0*/) {
 	// Check if have item on player reward chest
-	std::shared_ptr<RewardChest> rewardChest = player->getRewardChest();
+	const std::shared_ptr<RewardChest> &rewardChest = player->getRewardChest();
 	if (rewardChest->empty()) {
 		g_logger().debug("Reward chest is empty");
 		return RETURNVALUE_REWARDCHESTISEMPTY;
 	}
 
-	auto rewardItemsVector = player->getRewardsFromContainer(rewardChest->getContainer());
+	const auto &container = rewardChest->getContainer();
+	if (!container) {
+		return RETURNVALUE_REWARDCHESTISEMPTY;
+	}
+
+	auto rewardItemsVector = player->getRewardsFromContainer(container);
 	auto rewardCount = rewardItemsVector.size();
 	uint32_t movedRewardItems = 0;
 	std::string lootedItemsMessage;
@@ -9931,19 +9940,72 @@ void Game::removePlayer(const std::shared_ptr<Player> &player) {
 }
 
 void Game::addNpc(const std::shared_ptr<Npc> &npc) {
-	npcs[npc->getID()] = npc;
+	npcs.push_back(npc);
+	size_t index = npcs.size() - 1;
+	npcsNameIndex[npc->getLowerName()] = index;
+	npcsIdIndex[npc->getID()] = index;
 }
 
 void Game::removeNpc(const std::shared_ptr<Npc> &npc) {
-	npcs.erase(npc->getID());
+	if (!npc) {
+		return;
+	}
+
+	auto npcId = npc->getID();
+	const auto &npcLowerName = npc->getLowerName();
+	auto it = npcsIdIndex.find(npcId);
+	if (it != npcsIdIndex.end()) {
+		size_t index = it->second;
+		npcsNameIndex.erase(npcLowerName);
+		npcsIdIndex.erase(npcId);
+
+		if (index != npcs.size() - 1) {
+			std::swap(npcs[index], npcs.back());
+
+			const auto &movedNpc = npcs[index];
+			npcsNameIndex[movedNpc->getLowerName()] = index;
+			npcsIdIndex[movedNpc->getID()] = index;
+		}
+
+		npcs.pop_back();
+	}
 }
 
 void Game::addMonster(const std::shared_ptr<Monster> &monster) {
-	monsters[monster->getID()] = monster;
+	if (!monster) {
+		return;
+	}
+
+	const auto &lowerName = monster->getLowerName();
+	monsters.push_back(monster);
+	size_t index = monsters.size() - 1;
+	monstersNameIndex[lowerName] = index;
+	monstersIdIndex[monster->getID()] = index;
 }
 
 void Game::removeMonster(const std::shared_ptr<Monster> &monster) {
-	monsters.erase(monster->getID());
+	if (!monster) {
+		return;
+	}
+
+	auto monsterId = monster->getID();
+	const auto &monsterLowerName = monster->getLowerName();
+	auto it = monstersIdIndex.find(monsterId);
+	if (it != monstersIdIndex.end()) {
+		size_t index = it->second;
+		monstersNameIndex.erase(monsterLowerName);
+		monstersIdIndex.erase(monsterId);
+
+		if (index != monsters.size() - 1) {
+			std::swap(monsters[index], monsters.back());
+
+			const auto &movedMonster = monsters[index];
+			monstersNameIndex[movedMonster->getLowerName()] = index;
+			monstersIdIndex[movedMonster->getID()] = index;
+		}
+
+		monsters.pop_back();
+	}
 }
 
 std::shared_ptr<Guild> Game::getGuild(uint32_t id, bool allowOffline /* = flase */) const {
@@ -10152,7 +10214,7 @@ uint32_t Game::makeFiendishMonster(uint32_t forgeableMonsterId /* = 0*/, bool cr
 		forgeableMonsters.clear();
 		// If the forgeable monsters haven't been created
 		// Then we'll create them so they don't return in the next if (forgeableMonsters.empty())
-		for (const auto &[monsterId, monster] : monsters) {
+		for (const auto &monster : monsters) {
 			auto monsterTile = monster->getTile();
 			if (!monster || !monsterTile) {
 				continue;
@@ -10325,7 +10387,7 @@ void Game::updateForgeableMonsters() {
 	if (auto influencedLimit = g_configManager().getNumber(FORGE_INFLUENCED_CREATURES_LIMIT);
 	    forgeableMonsters.size() < influencedLimit) {
 		forgeableMonsters.clear();
-		for (const auto &[monsterId, monster] : monsters) {
+		for (const auto &monster : monsters) {
 			const auto &monsterTile = monster->getTile();
 			if (!monsterTile) {
 				continue;
@@ -10541,7 +10603,7 @@ void Game::playerRewardChestCollect(uint32_t playerId, const Position &pos, uint
 	}
 
 	// Updates the parent of the reward chest and reward containers to avoid memory usage after cleaning
-	auto playerRewardChest = player->getRewardChest();
+	const auto &playerRewardChest = player->getRewardChest();
 	if (playerRewardChest && playerRewardChest->empty()) {
 		player->sendCancelMessage(RETURNVALUE_REWARDCHESTISEMPTY);
 		return;
diff --git a/src/game/game.hpp b/src/game/game.hpp
index b16d1787d69..a59c7d13a70 100644
--- a/src/game/game.hpp
+++ b/src/game/game.hpp
@@ -522,10 +522,10 @@ class Game {
 	const phmap::parallel_flat_hash_map<uint32_t, std::shared_ptr<Player>> &getPlayers() const {
 		return players;
 	}
-	const std::map<uint32_t, std::shared_ptr<Monster>> &getMonsters() const {
+	const auto &getMonsters() const {
 		return monsters;
 	}
-	const std::map<uint32_t, std::shared_ptr<Npc>> &getNpcs() const {
+	const auto &getNpcs() const {
 		return npcs;
 	}
 
@@ -539,8 +539,8 @@ class Game {
 	void addNpc(const std::shared_ptr<Npc> &npc);
 	void removeNpc(const std::shared_ptr<Npc> &npc);
 
-	void addMonster(const std::shared_ptr<Monster> &npc);
-	void removeMonster(const std::shared_ptr<Monster> &npc);
+	void addMonster(const std::shared_ptr<Monster> &monster);
+	void removeMonster(const std::shared_ptr<Monster> &monster);
 
 	std::shared_ptr<Guild> getGuild(uint32_t id, bool allowOffline = false) const;
 	std::shared_ptr<Guild> getGuildByName(const std::string &name, bool allowOffline = false) const;
@@ -851,8 +851,16 @@ class Game {
 
 	std::shared_ptr<WildcardTreeNode> wildcardTree = nullptr;
 
-	std::map<uint32_t, std::shared_ptr<Npc>> npcs;
-	std::map<uint32_t, std::shared_ptr<Monster>> monsters;
+	std::vector<std::shared_ptr<Monster>> monsters;
+	// This works only for unique monsters (bosses, quest monsters, etc)
+	std::unordered_map<std::string, size_t> monstersNameIndex;
+	std::unordered_map<uint32_t, size_t> monstersIdIndex;
+
+	std::vector<std::shared_ptr<Npc>> npcs;
+	// This works only for unique npcs (quest npcs, etc)
+	std::unordered_map<std::string, size_t> npcsNameIndex;
+	std::unordered_map<uint32_t, size_t> npcsIdIndex;
+
 	std::vector<uint32_t> forgeableMonsters;
 
 	std::map<uint32_t, std::unique_ptr<TeamFinder>> teamFinderMap; // [leaderGUID] = TeamFinder*
diff --git a/src/game/zones/zone.hpp b/src/game/zones/zone.hpp
index a3af961bd7f..e13652e8b32 100644
--- a/src/game/zones/zone.hpp
+++ b/src/game/zones/zone.hpp
@@ -216,7 +216,7 @@ class Zone {
 	Position removeDestination = Position();
 	std::string name;
 	std::string monsterVariant;
-	std::unordered_set<Position> positions;
+	phmap::flat_hash_set<Position> positions;
 	uint32_t id = 0; // ID 0 is used in zones created dynamically from lua. The map editor uses IDs starting from 1 (automatically generated).
 
 	weak::set<Item> itemsCache;
diff --git a/src/io/io_bosstiary.cpp b/src/io/io_bosstiary.cpp
index 3e8a05524e6..57a9a85e294 100644
--- a/src/io/io_bosstiary.cpp
+++ b/src/io/io_bosstiary.cpp
@@ -20,46 +20,46 @@ IOBosstiary &IOBosstiary::getInstance() {
 }
 
 void IOBosstiary::loadBoostedBoss() {
-	Database &database = Database::getInstance();
-	std::ostringstream query;
-	query << "SELECT * FROM `boosted_boss`";
-	DBResult_ptr result = database.storeQuery(query.str());
-	if (!result) {
-		g_logger().error("[{}] Failed to detect boosted boss database. (CODE 01)", __FUNCTION__);
-		return;
-	}
-
-	auto date = result->getNumber<uint16_t>("date");
+	std::string query = R"SQL(
+		SELECT `date`, `boostname`, `raceid`, `looktypeEx`, `looktype`, 
+		       `lookfeet`, `looklegs`, `lookhead`, `lookbody`, 
+		       `lookaddons`, `lookmount`
+		FROM `boosted_boss`
+	)SQL";
+
+	DBResult_ptr result = g_database().storeQuery(query);
 	auto timeNow = getTimeNow();
 	auto time = localtime(&timeNow);
 	auto today = time->tm_mday;
 
-	auto bossMap = getBosstiaryMap();
+	const auto &bossMap = getBosstiaryMap();
 	if (bossMap.size() <= 1) {
 		g_logger().error("[{}] It is not possible to create a boosted boss with only one registered boss. (CODE 02)", __FUNCTION__);
 		return;
 	}
 
-	std::string bossName;
-	uint16_t bossId = 0;
-	if (date == today) {
-		bossName = result->getString("boostname");
-		bossId = result->getNumber<uint16_t>("raceid");
-		setBossBoostedName(bossName);
-		setBossBoostedId(bossId);
-		g_logger().info("Boosted boss: {}", bossName);
-		return;
+	if (!result) {
+		g_logger().warn("[{}] No boosted boss found in g_database(). A new one will be selected.", __FUNCTION__);
+	} else {
+		auto date = result->getNumber<uint16_t>("date");
+		if (date == today) {
+			std::string bossName = result->getString("boostname");
+			uint16_t bossId = result->getNumber<uint16_t>("raceid");
+			setBossBoostedName(bossName);
+			setBossBoostedId(bossId);
+			g_logger().info("Boosted boss: {}", bossName);
+			return;
+		}
 	}
 
 	// Filter only archfoe bosses
-	std::map<uint16_t, std::string> bossInfo;
-	for (auto [infoBossRaceId, infoBossName] : bossMap) {
-		const auto mType = getMonsterTypeByBossRaceId(infoBossRaceId);
+	std::vector<std::pair<uint16_t, std::string>> bossInfo;
+	for (const auto &[infoBossRaceId, infoBossName] : bossMap) {
+		const auto &mType = getMonsterTypeByBossRaceId(infoBossRaceId);
 		if (!mType || mType->info.bosstiaryRace != BosstiaryRarity_t::RARITY_ARCHFOE) {
 			continue;
 		}
-
-		bossInfo.try_emplace(infoBossRaceId, infoBossName);
+		bossInfo.emplace_back(infoBossRaceId, infoBossName);
 	}
 
 	// Check if not have archfoe registered boss
@@ -68,55 +68,39 @@ void IOBosstiary::loadBoostedBoss() {
 		return;
 	}
 
-	auto oldBossRace = result->getNumber<uint16_t>("raceid");
-	while (true) {
-		uint32_t randomIndex = uniform_random(0, static_cast<int32_t>(bossInfo.size()));
-		auto it = std::next(bossInfo.begin(), randomIndex);
-		if (it == bossInfo.end()) {
-			break;
-		}
-
-		const auto &[randomBossId, randomBossName] = *it;
-		if (randomBossId == oldBossRace) {
-			continue;
-		}
-
-		bossName = randomBossName;
-		bossId = randomBossId;
-		break;
+	const auto &[randomBossId, randomBossName] = bossInfo[uniform_random(0, static_cast<int32_t>(bossInfo.size() - 1))];
+	std::string bossName = randomBossName;
+	uint16_t bossId = randomBossId;
+
+	query = fmt::format(
+		"UPDATE `boosted_boss` SET `date` = '{}', `boostname` = {}, ",
+		today, g_database().escapeString(bossName)
+	);
+	if (const auto &bossType = getMonsterTypeByBossRaceId(bossId); bossType) {
+		query += fmt::format(
+			"`looktypeEx` = {}, `looktype` = {}, `lookfeet` = {}, `looklegs` = {}, "
+			"`lookhead` = {}, `lookbody` = {}, `lookaddons` = {}, `lookmount` = {}, ",
+			bossType->info.outfit.lookTypeEx, bossType->info.outfit.lookType,
+			bossType->info.outfit.lookFeet, bossType->info.outfit.lookLegs,
+			bossType->info.outfit.lookHead, bossType->info.outfit.lookBody,
+			bossType->info.outfit.lookAddons, bossType->info.outfit.lookMount
+		);
 	}
+	query += fmt::format("`raceid` = {}", bossId);
 
-	query.str(std::string());
-	query << "UPDATE `boosted_boss` SET ";
-	query << "`date` = '" << today << "',";
-	query << "`boostname` = " << database.escapeString(bossName) << ",";
-	if (const auto bossType = getMonsterTypeByBossRaceId(bossId);
-	    bossType) {
-		query << "`looktypeEx` = " << static_cast<int>(bossType->info.outfit.lookTypeEx) << ",";
-		query << "`looktype` = " << static_cast<int>(bossType->info.outfit.lookType) << ",";
-		query << "`lookfeet` = " << static_cast<int>(bossType->info.outfit.lookFeet) << ",";
-		query << "`looklegs` = " << static_cast<int>(bossType->info.outfit.lookLegs) << ",";
-		query << "`lookhead` = " << static_cast<int>(bossType->info.outfit.lookHead) << ",";
-		query << "`lookbody` = " << static_cast<int>(bossType->info.outfit.lookBody) << ",";
-		query << "`lookaddons` = " << static_cast<int>(bossType->info.outfit.lookAddons) << ",";
-		query << "`lookmount` = " << static_cast<int>(bossType->info.outfit.lookMount) << ",";
-	}
-	query << "`raceid` = '" << bossId << "'";
-	if (!database.executeQuery(query.str())) {
-		g_logger().error("[{}] Failed to detect boosted boss database. (CODE 03)", __FUNCTION__);
+	if (!g_database().executeQuery(query)) {
+		g_logger().error("[{}] Failed to update boosted boss in g_database(). (CODE 03)", __FUNCTION__);
 		return;
 	}
 
-	query.str(std::string());
-	query << "UPDATE `player_bosstiary` SET `bossIdSlotOne` = 0 WHERE `bossIdSlotOne` = " << bossId;
-	if (!database.executeQuery(query.str())) {
-		g_logger().error("[{}] Failed to reset players selected boss slot 1. (CODE 03)", __FUNCTION__);
+	query = fmt::format("UPDATE `player_bosstiary` SET `bossIdSlotOne` = 0 WHERE `bossIdSlotOne` = {}", bossId);
+	if (!g_database().executeQuery(query)) {
+		g_logger().error("[{}] Failed to reset players' selected boss slot 1. (CODE 03)", __FUNCTION__);
 	}
 
-	query.str(std::string());
-	query << "UPDATE `player_bosstiary` SET `bossIdSlotTwo` = 0 WHERE `bossIdSlotTwo` = " << bossId;
-	if (!database.executeQuery(query.str())) {
-		g_logger().error("[{}] Failed to reset players selected boss slot 1. (CODE 03)", __FUNCTION__);
+	query = fmt::format("UPDATE `player_bosstiary` SET `bossIdSlotTwo` = 0 WHERE `bossIdSlotTwo` = {}", bossId);
+	if (!g_database().executeQuery(query)) {
+		g_logger().error("[{}] Failed to reset players' selected boss slot 2. (CODE 03)", __FUNCTION__);
 	}
 
 	setBossBoostedName(bossName);
diff --git a/src/lua/functions/creatures/monster/monster_type_functions.cpp b/src/lua/functions/creatures/monster/monster_type_functions.cpp
index 07ce44b626c..8b2f4a5f314 100644
--- a/src/lua/functions/creatures/monster/monster_type_functions.cpp
+++ b/src/lua/functions/creatures/monster/monster_type_functions.cpp
@@ -1170,18 +1170,22 @@ int MonsterTypeFunctions::luaMonsterTypeGetCreatureEvents(lua_State* L) {
 int MonsterTypeFunctions::luaMonsterTypeRegisterEvent(lua_State* L) {
 	// monsterType:registerEvent(name)
 	const auto &monsterType = Lua::getUserdataShared<MonsterType>(L, 1);
-	if (monsterType) {
-		const auto eventName = Lua::getString(L, 2);
-		monsterType->info.scripts.insert(eventName);
-		for (const auto &[_, monster] : g_game().getMonsters()) {
-			if (monster->getMonsterType() == monsterType) {
-				monster->registerCreatureEvent(eventName);
-			}
-		}
-		Lua::pushBoolean(L, true);
-	} else {
+	if (!monsterType) {
 		lua_pushnil(L);
+		return 1;
 	}
+
+	const auto eventName = Lua::getString(L, 2);
+	monsterType->info.scripts.insert(eventName);
+
+	for (const auto &monster : g_game().getMonsters()) {
+		const auto monsterTypeCompare = monster->getMonsterType();
+		if (monsterTypeCompare == monsterType) {
+			monster->registerCreatureEvent(eventName);
+		}
+	}
+
+	Lua::pushBoolean(L, true);
 	return 1;
 }