Minecraft:Mob AI

This article describes the various components of a mob's AI that control its behavior.

Brain

Some mobs use a complex AI system called a brain. A mob's brain stores memories (data), a list of tasks that can be performed, and a list of sensors used to determine which tasks it can perform.

Sensor

Sensors are used to detect if a mob with a brain can perform certain tasks. Examples of sensors include, a sensor to detect if an armadillo should be scared, a sensor to detect the nearest player, and a sensor to detect if a mob is in water.

By default, sensors run once every 20 game ticks (1 second), although individual sensor classes can have a different scan rate. When a sensor runs, it updates its targeting conditions to match the mob's current Template:Attr attribute before performing its detection logic. The first execution of each sensor is delayed by a random number of ticks, preventing multiple sensors from running simultaneously.

List of Sensor Template:In

Sensor	Class	Uses
dummy	DummySensor	defaulted sensor type
nearest_items	NearestItemSensor	Template:Flatlist
nearest_living_entities	NearestLivingEntitySensor	Template:Flatlist
nearest_players	PlayerSensor	Template:Flatlist
nearest_bed	NearestBedSensor	Template:EntityLink
hurt_by	HurtBySensor	Template:Flatlist
villager_hostiles	VillagerHostilesSensor	Template:EntityLink
villager_babies	VillagerBabiesSensor	Template:EntityLink
secondary_pois	SecondaryPoiSensor	Template:EntityLink
golem_detected	GolemSensor	Template:EntityLink
armadillo_scare_detected	MobSensor	Template:EntityLink
piglin_specific_sensor	PiglinSpecificSensor	Template:EntityLink
piglin_brute_specific_sensor	PiglinBruteSpecificSensorregister	Template:EntityLink
hoglin_specific_sensor	HoglinSpecificSensor	Template:EntityLink
nearest_adult	AdultSensor	Template:Flatlist
nearest_adult_any_type	AdultSensor	Template:EntityLink
axolotl_attackables	AxolotlAttackablesSensor	Template:EntityLink
food_temptations	TemptingSensor	Template:Flatlist
frog_temptations	TemptingSensor	Template:Flatlist
nautilus_temptations	TemptingSensor	Template:Flatlist
frog_attackables	FrogAttackablesSensor	Template:EntityLink
is_in_water	IsInWaterSensor	Template:EntityLink
warden_entity_sensor	WardenEntitySensor	Template:EntityLink
breeze_attack_entity_sensor	BreezeAttackEntitySensor	Template:EntityLink

Sensor classes

Template:Expand sectionSensors classes are responsible for detecting a specific type of information and storing the results in one or more memory modules in a mob's brain. In the game's code, these classes are part of the package Template:Cd

Class	Memory requires	Do tick
DummySensor	None	Performs no actions
NearestItemSensor	Template:Cd	Find the Template:Tooltip item that: Is within a bounding box extending 32 blocks horizontally and 16 blocks vertically from the mob. Is within 32 blocks of the mob. The mob wants to pick up.Template:Fn Is in the mob's line of sight.Template:Fn The nearest matching item is stored in the Template:Cd memory. If no matching item is found, the memory is set to empty.
NearestLivingEntitySensor	Template:Cd and Template:Cd	Lists all other Minecraft:living entities that are alive and within a cuboid generated by the mob's hitbox expanded by its Template:Attr in all directions. Sorts the entities by Minecraft:Euclidean distance from the mob and stores the list in the Template:Cd memory. In Template:Cd, stores the entities from Template:Cd that:Template:Fn Are not a Minecraft:Spectator player or an invisible or marker Minecraft:armor stand. Are in the mob's line of sight.Template:Fn Are within a range of Template:Cd blocks of the mob, where Template:Cd is the Template:Attr.Template:Fn
PlayerSensor	Template:Cd, Template:Cd, Template:Cd and Template:Cd	List all non-Minecraft:Spectator players that are within a Minecraft:Euclidean distance of the mob's Template:Attr. Sorts the players by distance from the mob and stores the list in Template:Cd. From this list, it creates Template:Cd by filtering players using the mob's targeting conditions, which checks that the player is targetable, including being within follow range and in the mob's line of sight.Template:Fn If the resulting list is not empty, stores the first player in Template:Cd. Creates Template:Cd by filtering Template:Cd's list using the mob's attack targeting conditions: If the difficulty is Minecraft:peaceful, remove all players. Remove all players from Minecraft:creative mode. Remove all players from the same Minecraft:team as the mob. If the mob is the Minecraft:allay, remove the linked player. If the mob is a Minecraft:illager, Template:Cd is in the tag Template:Tag link, and neither the mob nor the player is on a team, remove the player. If the mob is a Minecraft:tamed animal, remove its owner and the players on the owner's team. If the resulting list is not empty, stores the first player in Template:Cd.
NearestBedSensor	Template:Cd	If the mob is a Minecraft:baby: Searches for POIs of type home (Minecraft:Bed) within 48 blocks of the mob. The sensor uses a cache to avoid repeatedly checking the same POIs and attempts to add up to 5 new beds to the cache during each scan. The sensor attempts to create a path to the found beds. If a path is found and can reach its target, and the target is a valid POI, stores the target's position in the mob's Template:Cd memory. If no reachable bed is found, and fewer than 5 POIs were checked, removes expired entries from the cache.Template:Fn
HurtBySensor	Template:Cd and Template:Cd	Checks the mob's last damageSource. If the mob has a last damage source, stores it in the Template:Cd memory. If the damage source was caused by a Minecraft:living entity, stores that entity in the Template:Cd memory. If the mob has no last damage source, removes the Template:Cd memory. If the entity stored in Template:Cd is no longer alive or is no longer in the same Minecraft:world, removes the Template:Cd memory.
VillagerHostilesSensor	Template:Cd and Template:Cd	Searches the Template:Cd memory for the nearest Minecraft:living entity matching one of the following hostile entity types and stores it in the Template:Cd memory: Template:EntityLink — within 8 blocks Template:EntityLink — within 12 blocks Template:EntityLink — within 8 blocks Template:EntityLink — within 12 blocks Template:EntityLink — within 15 blocks Template:EntityLink — within 12 blocks Template:EntityLink — within 8 blocks Template:EntityLink — within 10 blocks Template:EntityLink — within 10 blocks Template:EntityLink — within 8 blocks Template:EntityLink — within 8 blocks If no matching hostile entity is found, Template:Cd is set to empty.
VillagerBabiesSensor	Template:Cd	Finds all villagers that are babies from the mob's Template:Cd memory and stores them as a list in the Template:Cd memory. If no visible baby villagers are found, stores an empty list.
SecondaryPoiSensor
GolemSensor
MobSensor
PiglinSpecificSensor
PiglinBruteSpecificSensorregister
HoglinSpecificSensor
AdultSensor
AxolotlAttackablesSensor
TemptingSensor
FrogAttackablesSensor
IsInWaterSensor	Template:Cd	If the mob is touching the water, add the memory Template:Cd, otherwise remove the memory.
WardenEntitySensor
BreezeAttackEntitySensor

Task

Tasks are activities that mobs with brain AI systems can perform. Sensors are used to determine if a task can be performed, and tasks may use information stored in memories. Examples of tasks include a villager walking to its jobsite, a piglin admiring an item, or a warden emerging. Tasks have priorities, so tasks with a higher priority will over run tasks with lower priority, for example, if a zombie is wandering and it sees a player, it will switch tasks to attacking.

Memory

Memories are used to store data, and are used when mobs perform tasks. Examples of memories include a list of all visible mobs in range, the location of a villager's jobsite block, and any cooldowns the mob may have.

Control

Walking

Mobs movement on land varies whether it's hostile or passive. Hostile mobs will try to approach and attack the player when within their detection range, while most passive mobs will attempt to run away when attacked. Some mobs will also try to attack or run away from certain blocks or mobs.

Swimming

Mobs swimming works the same way as walking, but in water. While most mobs will just float on water or sink, some can properly swim like Minecraft:fish, Minecraft:drowned, Minecraft:dolphins, Minecraft:turtles, Minecraft:guardians and Minecraft:elder guardians.

Flying

Mobs flying works the same way as walking, but in air. Most mobs will just fall when suspended in air, with a few exceptions. Mobs with Minecraft:Slow Falling, Minecraft:levitation and the Minecraft:chicken don't fly normally but are able to float in mid-air. [[Minecraft::Category:Flying mobs]] contains a list of all mobs that can path find in air.

Goals

Goals are a simple AI system used primarily by mobs already existed before the brain AI. However, there are recent mobs that use both AIs simultaneously, for example, the Minecraft:happy ghast.

Goals can range from wandering around, opening doors, attacking another mob, and more. Each type of mob that uses goals has its own defined list of goals, and each goal has a priority. Mobs attempt to perform the lowest priority goal they can, and may switch goals if there is an opportunity to pursue a lower priority goal. For example, if a zombie is targeting and chasing a villager (priority of 3) and a player comes within the detection range of the zombie, the zombie may target and chase the player (priority of 2) instead.

List of goals

List of goals that are used by many different mobs.

List of Goals

Goal	Description	Notes
Active Target	Select an entity to target for chasing and attacking
Ambient Stand	Untamed horse bucks when player tries to ride it
Attack	Attack target
Attack with Owner	Tamed animal attacks a target mob attacked by owner
Avoid Entity	Mob runs away from another mob that it is afraid of (e.g. skeletons running from wolves)
Bow Attack	Attack target with bow
Breathe Air	Mob that can drown tries to move out of water
Cat Lie on Bed	Tamed cat lies down on bed
Cat Sit on Block	Cat sits on bed, chest, or furnace
Chase Boat	Chase after boat ridden by player	Unused
Crossbow Attack	Attack target with crossbow
Destroy Egg	Destroy turtle eggs
Disableable Follow Target	Raid entity stops following target	Unused
Dive Jump	Mob jumps up and dives down
Dolphin Jump	Dolphin jumps out of water
Door Interact	Mob tries to open a door
Eat Grass	Mob grazes on grass
Flee Sun	Move out of direct line-of-sight with sky during day
Float	Mob floats in water
Follow Flock Leader	Fish tries to follow the leader of a school of fish
Follow Mob	Mob follows another mob
Follow Owner	Tamed mob follows owner
Follow Parent	Baby mob follows its parent
Go to Walk Target	Mob walks to a target
Hold in Hands	Mob holds an item in its main hand
Horse Bond with Player	Horse attempts to bond with player attempting to tame it
Iron Golem Look	Iron golem looks at a villager
Iron Golem Wander Around	Iron golem wanders around village	uses points of interest
Llama Follow Caravan	Llamas form and follow a caravan
Leap At Target	Mob jumps towards target	cats, foxes, ocelots, spiders
Long Door Interact	Open a door, then close it after a delay
Look At Entity	Mob looks at another mob
Look At Player	Mob looks at player
Look At Trading Player	Villager or wandering trader looks at player while trading
Melee Attack	Mob paths to target and attacks
Move Into Water	Mob paths to water
Move Through Village	Mob moves between points of interest in a village
Move To Raid Center	Raiders move toward village after spawning
Move To Target Position	Mob paths to a specific block
Panic	Mob panics and runs away when damaged
Powder Snow Jump	Mob dives into powder snow	foxes
Prioritized Goal	Used to override the default priority of a goal
Projectile Attack	Mob attacks target with a projectile	arrow, spit, trident, potion, snow ball, wither skull, not fireballs
Raid Goal	Raiders target villagers
Random Look Around	Mob looks around in random directions
Random Stroll	Move to a nearby random position
Revenge	Target entity that attacked the mob
Run Around Like Crazy	Untamed horse runs around randomly when ridden by a player
Spear Use	Mob attacks target with spear
Swell	Creeper attempts to explode near its target
Tempt	Mob follows player holding breeding item
Water Avoiding Random Stroll	Move to a nearby random position, while actively avoiding water
Wander Around Far	Move to a random position, sometimes farther away than Wander Around goal
Zombie Attack	Attack goal for zombies and zombie variants

Lists of mob goals

Lists of goals and associated priorities for individual mobs.

Zombie

Goal	Priority	Notes
Revenge	1	Attack entity that damaged the zombie
Active Target - Player	2	Target the player
Zombie Attack	2	Attack current target
Active Target - Iron Golem	3	Target Iron Golem
Active Target - Merchant	3	Target Villager or Wandering Trader
Destroy Egg	4	Break turtle eggs
Active Target - Turtle	5	Target baby turtle
Wander Around Far	7
Look Around	8	Looks away from Entities
Look at Entity	8	Looks at nearest Entities

Pathfinding

Pathfinding penalties

File:Zombified piglin pathing 1.png

Zombified piglin starts pathfinding to a Minecraft:turtle egg

File:Zombified pigling pathing 2.png

Due to pathfinding penalties, the zombified piglin takes an indirect path to the turtle egg, pathing through wither roses and taking damage, instead of pathing through the lava or magma blocks, which do not damage the zombified piglin

When pathfinding to a target, mobs will sometimes avoid certain blocks (usually blocks that cause damage or slow the mob down). These blocks have a penalty associated with them. Generally, mobs try to path through blocks with the smallest penalty. There are some blocks that most mobs cannot path through; these all have a penalty of -1.

The following table is a list of all pathfinding penalties and their default values. Each type of pathfinding (land, water, air) uses its own subset of these penalties. Some mobs override these default values.

Penalty type	Penalty	Description
blocked	-1	can't pathfind through block (most full solid blocks)
powder snow	-1	Template:BlockLink
fence	-1	Template:BlockLink Template:BlockLink Template:BlockLink (closed)
lava	-1	Template:BlockLink
unpassable rail	-1	Template:BlockLink
damage - other	-1	Template:BlockLink Template:BlockLink
closed wood door	-1	Template:BlockLink
closed iron door	-1	Template:BlockLink
open	0	Template:BlockLink Template:BlockLink Template:BlockLink
walkable	0	Template:BlockLink with pressure plate on top (under the mob)
walkable door	0	a door the mob can open
trapdoor	0	Template:BlockLink Template:BlockLink Template:BlockLink
danger - powder snow	0	neighboring block is Template:BlockLink
open door	0	open wood or iron door
cocoa	0	Template:BlockLink
damage - cautious	0	Template:BlockLink Template:BlockLink
danger - trapdoor	0	neighboring block is Template:BlockLink
breach water	4	there is an air block above a water block
water	8	Template:BlockLink
water border	8	neighboring block is Template:BlockLink
danger - fire	8	neighboring block is: Template:BlockLink Template:BlockLink Template:BlockLink Template:BlockLink Template:BlockLink
danger - other	8	neighboring block is: Template:BlockLink Template:BlockLink
honey	8	Template:BlockLink
damage - fire	16	Template:BlockLink Template:BlockLink Template:BlockLink Template:BlockLink Template:BlockLink

Mob pathfinding penalty overrides

The following mobs override the default pathfinding penalty for some blocks:

Mob	Penalty Type	Penalty
Template:EntityLink	water	0
Template:EntityLink	damage - fire	-1
	water	-1
	cocoa	-1
	fence	-1
	water border	16
Template:EntityLink	water	0
Template:EntityLink	danger - other	0
	damage - other	0
Template:EntityLink	trapdoor	-1
	water	4
Template:EntityLink	powder snow	-1
	danger - powder snow	-1
Template:EntityLink Template:EntityLink	damage-fire	-1
	danger - fire	16
Template:EntityLink	danger-fire	-1
	damage - fire	-1
	cocoa	-1
Template:EntityLink	water	-1
	danger - powder snow	-1
	damage - cautious	-1
Template:EntityLink	water	-1
	lava	0
	danger - fire	0
	damage - fire	0
Template:EntityLink	close iron door	-1
	closed wood door	-1
	open door	-1
	water	0
Template:EntityLink	powder snow	-1
	danger - powder snow	-1
Template:EntityLink Template:EntityLink	damage - fire	-1
	danger - fire	16
Template:EntityLink	water	-1
	danger - fire	8
	damage - fire	8
	lava	8
Template:EntityLink	danger - trapdoor	-1
	damage - fire	-1
Template:EntityLink	water	0
Template:EntityLink	water	-1
Template:EntityLink	water	0
Template:EntityLink	leaves	0
Template:EntityLink	unpassable rail	0
	damage - fire	0
	danger - fire	0
	damage - other	8
	powder snow	8
	lava	8
water creatures	water	0
Template:EntityLink	lava	8
Template:EntityLink	lava	8
animal	damage - fire	-1
	danger - fire

Pathfinding on land

• All entities Move based off of random targets that are generated every tick with a priority toward their entity specific goals.
• These targets can be located anywhere in 3D space within the entity range and are only every generated when wandering or when they have no goals.
• For every target a path is generated; with the entity preferring the path with the lowest score regarding the Pathfinding penalties.
• If an entity cannot take any paths with a low enough score, or any paths without a score of -1 the entity will not move until one is found.
• If an entity's target is located inside a block (including water), the target is moved to the nearest air block above it.

This means, every entity when wandering will always prefer to pathfind to a block with the most blocks below it within range.

Due to the higher chance that a target will be generated within the blocks below it and moved up to the nearest air block above before generating a path.

Pathfinding in water

• Pathfinding in water is roughly the same as land, however, most entities, excluding fish and drowned, will bounce on the surface preferring land due to the Pathfinding penalties of water.

Pathfinding in air

• Pathfinding in air is roughly the same as land, however, there are few entities that can pathfind to air.

See also

• Minecraft:Mob infighting