---
title: "Creature zoo: API"
package: "@phaser-ae/creature-zoo"
tier: Pro
version: 3.0.0-0
released: 2026-10-19
updated: 2026-10-19
description: "Wildlife and monsters for a 3D landscape, from flocks and dragons to burrowing worms and sea creatures, each kind a data record that the zoo moves and makes choices for."
url: https://phaser.io/packs/creature-zoo/api
site: Phaser - https://phaser.io
---

# Creature zoo: API

`@phaser-ae/creature-zoo` — Data-driven creatures for a 3D world over a heightfield: flocks, flyers, worms, serpents, walkers and sea monsters that hunt, stand off, eat, grow and lay eggs.

## The pack

### `creatureZoo`

```ts
function creatureZoo(): Pack<{ creatureZoo: typeof api }>
```

Install the creature-zoo API (`game.creatureZoo`).

## Classes

### `Zoo`

```ts
class Zoo
```

A herd of creatures on a ground, kept in `list` (plain data the game saves).

- `constructor( /** The kinds, by id. */ readonly kinds: Readonly<Record<string, CreatureKind>>, /** The game. */ readonly host: ZooHost, /** The creatures (the game's own array: it is saved with the game's state). */ public list: Creature[], )`
- `sizeOf(k: Creature): number` — A creature's current size (eaters grow 40% a stage).
- `attackOf(k: Creature, kind: CreatureKind): CreatureAttack` — Its attack now: a grown stage's, or the base one.
- `spawn(kind: CreatureKind, x: number, z: number, herd: number): Creature` — One creature at (x, z), in herd `herd`.
- `spawnGroup(kind: CreatureKind, avoid: { x: number; z: number }): void` — A herd of `kind.group` creatures somewhere it can live, well away from `avoid`.
- `step(dt: number): void` — One step: choose targets, move, trail segments, eat and grow, lay eggs, attack.

## Types

### `Creature`

```ts
interface Creature
```

A creature in play.

- `id: number` — Unique number among all entities.
- `kind: string` — Id of its `CreatureKind`, the key in the zoo's `kinds`.
- `x: number` — World x.
- `y: number` — World y, up.
- `z: number` — World z.
- `vx: number` — Velocity along x in world units per second.
- `vy: number` — Velocity along y (up) in world units per second.
- `vz: number` — Velocity along z in world units per second.
- `yaw: number` — Heading in radians, with the carpet's convention: 0 looks along +z and increasing turns right.
- `hp: number` — Hit points left; it dies at 0 and releases its `mana`.
- `mana: number` — Mana it holds (released on death).
- `stage: number` — Growth stage (0 = the base).
- `herd: number` — Herd/flock id.
- `angry: boolean` — Has turned hostile (non-aggressive kinds after being hit).
- `target: string` — What it is after: the host's reference for the target (mana-conquest: "w:3", "c:2", "b:5", "k:9"), or "".
- `cool: number` — Seconds until its next attack.
- `away: number` — Seconds left away (teleported), or 0.
- `rise: number` — A worm's or kraken's rise 0..1.
- `trail: Array<{ x: number; y: number; z: number }>` — Trail of earlier positions (segments follow it).
- `owner: number` — The team it fights for (mana-conquest: the wizard of an undead army), or -1 for wild.
- `age: number` — Seconds it has lived.
- `homeX: number` — World x of the spot it wanders around; a flock's anchor drifts.
- `homeZ: number` — World z of the spot it wanders around; a flock's anchor drifts.
- `alive: boolean` — False once dead.
- `lay: number` — Laying timer (grown crabs).

### `CreatureAttack`

```ts
interface CreatureAttack
```

A creature's attack.

- `kind: "melee" | (string & {})` — `melee` (claws or stings at touching range: the creature closes in) or a name the host carries out as it likes (mana-conquest's: fireball, rapid, boulder, arrow, lightning, meteor); a ranged attack stands off.
- `damage: number` — Damage of each hit to what it strikes.
- `range: number` — Reach (world units).
- `every: number` — Seconds between attacks.

### `CreatureKind`

```ts
interface CreatureKind
```

A kind of creature.

- `id: string` — Unique kind name: the key in the zoo's `kinds`, and what a creature's `kind` and the host's own lists refer to.
- `name: string` — Display name.
- `hp: number` — Hit points at full health.
- `mana: number` — Mana released when it dies (split into orbs).
- `size: number` — Body size (world units across).
- `speed: number` — Cruising speed (world units/s).
- `motion: CreatureMotion` — How it moves and fights: flocks, flyers, worms, serpents, walkers or sea creatures.
- `altitude: number` — Flying height over the ground (flyers).
- `attack: CreatureAttack` — Its base attack; a `grows` stage replaces it.
- `sight: number` — Notices targets within this distance.
- `aggressive: boolean` — False: harmless until something hurts it (the griffin), then its whole herd turns.
- `targets: string[]` — What it goes for: the classes of target the host offers (mana-conquest: wizard, castle, balloon, creature).
- `humanOnly?: boolean` — The host's own flag: of the wizards, it goes only for the human player (Magic Carpet's bees).
- `group: [number, number]` — How many come together.
- `regen?: number` — Health regained per second.
- `eatsMana?: boolean` — Eats loose mana orbs it reaches (the mana is held and released on death).
- `grows?: { per: number; stages: CreatureAttack[]; layEvery?: number }` — Grows as it eats: each stage needs this much mana; stage attacks replace the base attack.
- `stealsMana?: number` — The host's own rule: steals this much personal mana from a wizard it hits.
- `teleportsAt?: number` — The host's own rule: teleports away when hurt below this fraction of its health and comes back restored.
- `converts?: string` — The host's own rule: a victim it kills rises as one of this kind (skeletons).
- `seesInvisible?: boolean` — The host's own rule: sees invisible wizards.
- `ignoresRebound?: boolean` — The host's own rule: its fireballs cannot be rebounded.
- `segments?: number` — Segments of a worm or serpent.

### `CreatureMotion`

```ts
type CreatureMotion = /** Flies in a loose flock that wanders and swoops on targets (vultures, bees, griffins). */ | "flock" /** Flies alone, circling and diving (genie, wyvern). */ | "flyer" /** A segmented body that swims through the land, rearing up to strike (worms). */ | "worm" /** A segmented body that flies (MC1's dragon). */ | "serpent" /** Walks the land and will not cross water (apes, trolls, skeletons, crabs, emu riders). */ | "walker" /** Lives under the sea and rises to strike (kraken). */ | "sea"
```

How a creature moves.

### `ZooFood`

```ts
interface ZooFood
```

Food an eater can reach (mana orbs).

- `id: number` — The host's id.
- `x: number` — World x.
- `y: number` — World y.
- `z: number` — World z.
- `amount: number` — What eating it is worth.
- `alive: boolean` — Still there.

### `ZooGround`

```ts
interface ZooGround
```

What the zoo needs of the ground: a wrapping height field over a sea (a `torus-land` Land answers all of it).

- `readonly cell: number` — World units per cell.
- `readonly size: number` — World units across.
- `readonly sea: number` — The sea's level.
- `groundAt(x: number, z: number): number` — The height to stay above: land, or the sea over it.
- `heightAt(x: number, z: number): number` — The land's own height (the sea bed under water).
- `isWater(x: number, z: number): boolean` — Under the sea.
- `wrap(v: number): number` — Fold a coordinate onto the world.
- `delta(a: number, b: number): number` — Shortest `b - a` across the wrap.
- `distance(ax: number, az: number, bx: number, bz: number): number` — Distance across the wrap.

### `ZooHost`

```ts
interface ZooHost
```

What a zoo asks of its game.

- `readonly ground: ZooGround` — The ground.
- `rand(): number` — The game's seeded random numbers in [0, 1).
- `id(): number` — A fresh entity id.
- `targets(k: Creature, kind: CreatureKind): Iterable<ZooTarget>` — Every target this creature could go for (filtered by `kind.targets` and the game's own rules).
- `locate(ref: string): { x: number; y: number; z: number } | null` — Where a target is now, or null when it is gone.
- `keep?(k: Creature, ref: string): boolean` — Keep chasing this target even though another is nearer (mana-conquest: a grudge against a wizard). Default no.
- `attack(k: Creature, kind: CreatureKind, atk: CreatureAttack, at: { x: number; y: number; z: number }, to: { x: number; y: number; z: number }): void` — Carry out an attack from `at` at the target at `to`: the game owns damage and projectiles.
- `food?(): Iterable<ZooFood>` — Food on the ground, for eaters.
- `eat?(k: Creature, food: ZooFood): void` — An eater reached this food: the game removes it (the zoo adds its amount and grows the creature).
- `laid?(young: Creature): void` — A grown creature laid an egg that hatched here.

### `ZooTarget`

```ts
interface ZooTarget
```

A target the host offers a creature.

- `ref: string` — The host's reference for it (kept in `Creature.target`).
- `x: number` — World x.
- `y: number` — World y.
- `z: number` — World z.
- `team: number` — Its team: a creature never goes for its own.

---

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