Monster

The term Monster refers to a category of mobs that are mainly hostile to the player.

Common properties

Mobs mentioned on this page share the following properties:

They are classified as Monster or Enemy in the game code and spawning mechanics.
Most of them are attacked by Iron Golems and Snow Golems.
They don't spawn naturally in Peaceful difficulty.
They prevent the player from sleeping.
They are attacked by conduits.
Most of them are triggers in the "Monster Hunter" advancement and "Monsters Hunted" challenge.

Additionally, in Bedrock Edition, the ID of the undead horses are part of the undead category, which is a subclass of the monster category.

This mob is hostile, but is not treated as a monster in the game code - rather as an animal.

These mobs are monsters in the game code, but are not treated as such in game:

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Icon		Achievement	In-game description	Actual requirements (if different)	Gamerscore earned	Trophy type (PS)
PS4	Other	Achievement	In-game description	Actual requirements (if different)	Gamerscore earned	Trophy type (PS)

Icon	Advancement	In-game description	Actual requirements (if different)
	Monster Hunter	Kill any hostile monster	Kill one of these 37 mobs:[hide] Blaze Bogged Breeze Cave Spider Creaking (by destroying its creaking heart) Creeper Drowned Elder Guardian Ender Dragon Enderman Endermite Evoker Ghast Guardian Hoglin Husk Magma Cube Phantom Piglin Piglin Brute Pillager Ravager Shulker Silverfish Skeleton Slime Spider Stray Vex Vindicator Witch Wither Wither Skeleton Zoglin Zombie Zombie Villager Zombified Piglin Other mobs may be killed, but are ignored for this advancement.
	Monsters Hunted	Kill one of every hostile monster	Kill each of these 37 mobs:[hide] Blaze Bogged Breeze Cave Spider Creaking (by destroying its creaking heart) Creeper Drowned Elder Guardian Ender Dragon Enderman Endermite Evoker Ghast Guardian Hoglin Husk Magma Cube Phantom Piglin Piglin Brute Pillager Ravager Shulker Silverfish Skeleton Slime Spider Stray Vex Vindicator Witch Wither Wither Skeleton Zoglin Zombie Zombie Villager Zombified Piglin Other mobs may be killed, but are ignored for this advancement.

The warden is the only monster that does not count towards the Monster Hunter advancement or Monsters Hunted challenge.
- The reason for this is because the warden is not intended to be slain, and is instead meant to be evaded.

Mobs that are classified as monsters in the game code as of Java Edition 1.21 apart from the bogged.
A creeper in a stronghold.
A zombie breaking a door.
Some skeletons in a soul sand valley.
A spider retaliating against a skeleton.
Two witches in a swamp.
A witch in her hut.
A haunting of endermen in the End.
Slimes inside a cave.
A blaze and a wither skeleton in a Nether fortress.