core

const core: Readonly<{ systems: CoreHandles<FlatSystemHandles<object & object & object & object>>; }>

The core: the step’s own machinery, which every world runs. A game never lists it, omits it or replaces it, and anchors to its systems by their handles: after: [core.systems.physics]. Every other system is an engine plugin’s, reached on its factory, behaviours.systems.chase, or a game’s own.

The step runs them in this order with every engine plugin listed:

Phase	System	Plugin	Runs on	What it does
input	tracks.copyInput	tracks()	room and page	Copies the player’s steer and jump into each track mover under the client’s authority.
input	core.copyInput	the core	room and page	Copies the player’s input into each entity the player controls under the client’s authority.
input	characters.walk	characters()	room and page, predicted system	Sends each character a walk command names along the navmesh to its point, and stops each a stop command names: on the sender’s page at once, and on the room on the same tick.
input	abilities.approach	abilities()	room and page	Walks each caster toward the target of its pending cast, as a click to walk does, and stops it once the target is in range.
motion	stats.expireModifiers	stats()	room and page	Counts down each timed stat modifier, and drops it once spent.
motion	stats.copyFields	stats()	room and page, predicted system	Sets each field a stat is registered to from the entity’s stat.
motion	core.move	the core	room and page, predicted system	Moves each entity by its velocity.
motion	core.blendCorrections	the core	page	Closes the drawn offset of each character the room corrected, so the correction eases in.
motion	tracks.move	tracks()	room and page	Moves each track mover along its track, and stands its entity there.
motion	tracks.markTriggers	tracks()	room and page	Marks the track triggers a mover stands in, enters or leaves.
rules	core.advanceDayClock	the core	room	Walks each World’s day clock on by the hours the step’s seconds buy at its day length.
rules	cooldowns.countDown	cooldowns()	room and page, predicted system	Counts down each entity’s cooldowns, and ends each: a character’s on the player’s page too, which predicts them.
rules	inventory.takeItemCommands	inventory()	room	Runs each item verb a player asked of her character.
rules	inventory.useItems	inventory()	room	Runs the uses asked of each entity’s items.
rules	behaviours.spin	behaviours()	room and page	Turns each spinning entity round y.
rules	behaviours.bob	behaviours()	room and page	Rises and falls each bobbing entity.
rules	behaviours.pickup	behaviours()	room	Credits each pickup a player’s character reaches to that character’s wallet, and removes it.
rules	inventory.loot	inventory()	room	Puts each loot a player’s character reaches into that character’s bag as far as it fits.
rules	behaviours.interact	behaviours()	room and page	Marks each Interact a character stands near.
rules	behaviours.takeInteracts	behaviours()	room	Takes each interact command within its Interact’s reach.
rules	behaviours.trigger	behaviours()	room and page	Marks each trigger a character stands within, and raises its enter and exit.
rules	behaviours.capHealth	behaviours()	room	Clamps each health under its maximum.
rules	behaviours.reapDead	behaviours()	room	Removes each entity at zero health, and downs a player’s character or one with a respawn instead.
rules	behaviours.respawnDowned	behaviours()	room	Stands each downed entity with a respawn that is no player’s character, such as a crate, an NPC or a kart, again once its wait is spent.
rules	characters.respawn	characters()	room	Stands each downed player’s character, one a player may control that the character controller moves, again once its respawn’s wait is spent, and runs each plugin’s onCharacterRespawn.
rules	behaviours.chase	behaviours()	room	Points each chaser’s velocity at the nearest character it accepts, and parts chasers that overlap.
rules	resources.regenerate	resources()	room and page, predicted system	Regenerates or decays each resource, such as mana, between 0 and its maximum: a character’s on the player’s page too, which predicts it, health aside.
rules	abilities.cast	abilities()	room and page, predicted system	Starts or refuses each cast a player sent, and winds each cast down to its release, its cancel or its fizzle: on her page too, up to the release’s outcomes, which the room alone decides.
rules	weapons.flyProjectiles	weapons()	room and page	Flies each projectile, and damages the first target it meets.
rules	npcs.takePicks	npcs()	room	Takes each pick a player sent in her conversation.
rules	rounds.takeRequests	rounds()	room	Takes each page’s start and restart of the round.
rules	rounds.advance	rounds()	room and page	Scores each round in play and counts its clock down to a win or a loss.
rules	npcs.converse	npcs()	room and page	Starts a conversation on each press of an NPC with a Dialog, and moves each conversation on.
rules	npcs.runRoutines	npcs()	room and page	Sends each NPC’s routine what happened to it, and does the step it is on.
rules	machines.advance	machines()	room and page	Counts each state machine’s wait, and moves on each one whose wait is spent or whose when holds.
rules	abilities.keepRefusals	abilities()	room and page	Files each cast refusal for the devtools’ ability inspector.
physics	characters.aim	characters()	room and page, predicted system	Writes each character’s strafe and the pitch its input aims at into its pose, which other pages draw.
physics	characters.npcMovement	characters()	room	Steers each character no player controls along its path, and moves it with moveCharacter, or along the navmesh for a chaser that does not walk, bases before riders.
physics	characters.movement	characters()	room and page, predicted system	Steers each player’s character on its input, or along its path while that input is not steering, and moves it with moveCharacter, bases before riders.
physics	characters.countDown	characters()	room and page, predicted system	Counts down each character’s timed speed modifiers, and ends each: on the player’s page too, which predicts them.
physics	core.physics	the core	room and page	Steps the physics scene once: builds and drops bodies, places each stand-in at its streamed pose, hands each body moveAndSlide moved its move as a kinematic target, steps Rapier, reads each dynamic body back, and destroys what fell out of the world.
physics	core.follow	the core	room and page, predicted system	Stands each attached entity at its parent’s pose and its offset, parents before children.
physics	core.restColliders	the core	room and page	Marks each kinematic collider that has stood still half a second, so the navmesh bakes it in, and unmarks it as it moves.

“Runs on” is where a system runs in a game with a room, as its entry’s runsOn says; a predicted system also runs on her page’s replay of her steps. A game with no room runs every system.