Powers

JS-defined powers let you write ability logic entirely in JavaScript. Register via OriginsJS.powerBuilder() in startup_scripts/.

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PowerBuilder

Obtain a builder with OriginsJS.powerBuilder(id), chain callback methods, then call .register().

Methods

Method	Callback Signature	Trigger
.grant(cb)	(LivingEntity, JsonObject) => void	Power gained
.revoke(cb)	(LivingEntity, JsonObject) => void	Power lost
.tick(cb)	(LivingEntity, JsonObject) => void	Every tick
.active(cb)	(LivingEntity, JsonObject) => void	Active key pressed
.inactive(cb)	(LivingEntity, JsonObject) => void	Active key released
.isActive(pred)	(LivingEntity, JsonObject) => boolean	Whether the power is active
.register()	—	Finalize (must be called last)

caution

active and inactive callbacks have limited support on 1.20.1 — they are not true overrides of Apoli's lifecycle. Their behavior depends on external key-binding integration.

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Regeneration Power

OriginsJS.powerBuilder("regeneration_power")
    .tick((entity, params) => {
        let amount = params.has("amount") ? params.get("amount").getAsFloat() : 0.5;
        if (entity.getHealth() < entity.getMaxHealth()) {
            entity.heal(amount);
        }
    })
    .register();

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Toggle Night Vision

let nightVisionActive = new java.util.HashMap();

OriginsJS.powerBuilder("night_vision_toggle")
    .active((entity, params) => {
        entity.addEffect(new net.minecraft.world.effect.MobEffectInstance(
            net.minecraft.world.effect.MobEffects.NIGHT_VISION,
            999999, 0, false, false
        ));
        nightVisionActive.put(entity.getUUID(), true);
    })
    .inactive((entity, params) => {
        entity.removeEffect(net.minecraft.world.effect.MobEffects.NIGHT_VISION);
        nightVisionActive.put(entity.getUUID(), false);
    })
    .isActive((entity, params) =>
        nightVisionActive.getOrDefault(entity.getUUID(), false))
    .register();

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Underwater Speed

OriginsJS.powerBuilder("underwater_speed")
    .tick((entity, params) => {
        if (entity.isUnderWater()) {
            entity.addEffect(new net.minecraft.world.effect.MobEffectInstance(
                net.minecraft.world.effect.MobEffects.MOVEMENT_SPEED,
                20, 1, false, false
            ));
        }
    })
    .grant((entity, params) => {
        if (entity.isPlayer()) entity.tell("You feel the power of the water!");
    })
    .revoke((entity, params) => {
        entity.removeEffect(net.minecraft.world.effect.MobEffects.MOVEMENT_SPEED);
    })
    .register();

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JSON Format

{
    "type": "origins_js:js_power",
    "id": "regeneration_power",
    "params": { "amount": 1.0 }
}

• type — always origins_js:js_power
• id — matches the builder's ID
• params — optional JsonObject passed to every callback