Modding:Entity Behaviors

Using Entity Behaviors

Inside the entity json file, entity behaviors can be added to the client section, server section, or both. For example, here is the controlledphysics behavior from deer.json, added to both the client and server sections. This shows the pre-1.20 style of including the behavior on both sides. Note that the properties are added directly to the behavior object, instead of in a properties object like with blocks and items. Also note that the builtin entity behavior names are all lower case, unlike block and collectible behaviors.

	client: {
        ...
		behaviors: [
            ...
			{
                code: "controlledphysics",
                "stepHeightByType": {
		    		"deer-pampas-*": 2.1251,
	    			"deer-pudu-*": 2.1251,
    				"deer-redbrocket-*": 2.1251,
				    "*": 3.1251
			    } 
            },
            ...
		],
        ...
	},
	server: {
        ...
		behaviors: [
            ...
			{
                code: "controlledphysics",
                "stepHeightByType": {
		    		"deer-pampas-*": 2.1251,
	    			"deer-pudu-*": 2.1251,
    				"deer-redbrocket-*": 2.1251,
				    "*": 3.1251
			    } 
            },
            ...
		],
        ...
	},

In 1.20, the behaviorConfigs section was added. For behaviors that added to both sections, the properties may be specified in the behaviorConfigs section to avoid duplicating the properties in both the client and server section. Here is the above example using behaviorConfigs.

	behaviorConfigs: {
		"controlledphysics": { 
			"stepHeightByType": {
				"deer-pampas-*": 2.1251,
				"deer-pudu-*": 2.1251,
				"deer-redbrocket-*": 2.1251,
				"*": 3.1251
			}
		},
        ...
	},
	client: {
        ...
		behaviors: [
            ...
			{ code: "controlledphysics" },
            ...
		],
        ...
	},
	server: {
        ...
		behaviors: [
            ...
			{ code: "controlledphysics" },
            ...
		],
        ...
	},

All Behaviors

Here is a table containing all the entity behaviors of the base game. Of course mods can, and are encouraged to add new behaviors.

Behavior Name	Explanation	Example entities	Properties	Side
activitydriven		villager		Server
aimingaccuracy	Adds aiming inaccuracy when sprinting, jumping, etc.	player playerbot		Universal
antlergrowth		deer animals with horns	beginGrowMonth c1 c2 c3 growDurationMonths grownDurationMonths noItemDrop overrideType shedDurationMonths variants	Universal
armorstandinventory		armorstand		Universal
bodytemperature		player		Universal
boss		eidolon-immobolized	musicTrack	Client
breathe	The entity will need to breathe and therefore suffocate in other blocks (for example sand).	player - both sides most animals - server only		Universal
collectitems	The entity collections items laying around on the ground.	player bot racoon		Server
commandable		erel locust-hacked mechhelper		Universal
controlledphysics	Add physics to an entity that can move on its own.	most entities	stepHeight = 0.6	Universal
conversable		libraryresonator trader villager	dialogue	Universal
deaddecay		animals	decayedBlock hoursToDecay	Server
despawn	The entity will despawn under given circumstances.	projectiles - server only animals - both sides	afterDays belowLightLevel minPlayerDistance minSeconds = 30	Universal
drunktyping		player		Client
emotionstates	Adds emotion states with a given chance. As an example, it can be used to make an animal "hungry" (aggressive) and "saturated" (passive).	most animals most humanoids	states	Server
extraskinnable		player playerbot		Universal
floatupwhenstuck	Float up the entity if it gets stuck in a block.	item most animals	onlyWhenDead = false pushVelocityMul = 1	Universal
grow	The entity will grow and eventually turn into one of its adults.	pig-wild-piglet most baby animals	hoursToGrow = 96 adultEntityCodes = []	Server
harvestable	Handles calculating the entity drops, updating the animal weight, adjusting the drops based on weight, and the harvest inventory.	wolf harvestable animals	drops duration fixedweight quantitySlots	Universal
health	Applies custom health to the entity. Means the entity can be hurt as well.	bear player most entities	currenthealth = 20 maxhealth = 20 basemaxhealth = 20	Server
hidewatersurface		boat	hideWaterElement	Client
hunger	Adds saturation and hunger, the entity needs to eat in order to stay alive.	player	currentsaturation = 1200 maxsaturation = 1200 saturationlossdelay = 60 * 24 currentfruitLevel = 0 currentvegetableLevel = 0 currentgrainLevel = 0 currentproteinLevel = 0 currentdairyLevel = 0	Server
idleanimations		player		Universal
interpolateposition	Interpolates entity position and rotate. Smooths out the animations. It's a visual effect, therefore not available on server side.	most entities		Client
milkable		goal sheep-bighorn-female		Universal
mortallywoundable		elk-tamed	whenBelowHealth	Universal
mouthinventory		racoon	acceptStacks	Universal
multiply	A pack of wolves for example grows in size over time (new babies are born). When installed on the client side, it shows portions eaten info text.	hostile animals - server only farm animals - both sides	eatAnyway growthCapEntityCodes growthCapQuantity growthCapRange pregnancyDays = 3.0 quantityPerDay spawnEntityCode requiresNearbyEntityCode requiresNearbyEntityRange = 5 multiplyCooldownDaysMin = 6 multiplyCooldownDaysMax = 12 portionsEatenForMultiply = 3 spawnEntityCode spawnEntityCodes spawnQuantityMin = 1 spawnQuantityMax = 2 requiresFood = true	Universal
multiplybase		chicken-hen	multiplyCooldownDaysMax multiplyCooldownDaysMin portionsEatenForMultiply	Universal
nametag	Adds a name tag to the entity which will be displayed above the entity.	player playerbot trader villager	renderRange = 99 selectFromRandomName showtagonlywhentargeted = false	Universal
openablecontainer		erel mechhelper		Universal
passivephysics	Adds physics an entity that cannot move on its own, but it still affected by things like wind and gravity.	item thrownstone most projectiles	waterDragFactor = 1 airDragFallingFactor = 1 groundDragFactor = 1 gravityFactor = 1	Universal
passivephysicsmultibox		boat boat-construction		Universal
pettable		chicken farm animals fox wolf	minGeneration	Server
placeblock	The entity will place one of the given block codes from time to time.	hen - prior to 1.15 update	minHourDelay = 8 * 24 maxHourDelay = 15*24 blockCodes = []	Server
playerinventory		player		Universal
playerphysics	Makes an entity controllable by a player. Because this inherits from controlledphysics, do not add both to an entity.	player	stepHeight = 0.6	Universal
repulseagents	Pushes other entities back.	most entities	movable = true	Universal
reviveondeath		eidolon-immobilized trader villager	maxHours minHours	Server
rideable		elk-tamed		Universal
rideableaccessories		boat elk-tamed		Universal
ropetieable		elk-tamed farm animals wolf	minGeneration	Universal
seatable		boat		Universal
selectionboxes		boat boat-construction elk-tamed		Universal
seraphinventory		armorstand-aged playerbot		Universal
taskai	Allows you to specify tasks.	most entities	aitasks	Server
tiredness	The entity will get tired over time. When it is sufficiently tired, it may sleep in a bed.	player	currenttiredness = 0	Universal
villagerinventory		villager		Both

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