ExampleStatusEffects.java

package com.example.examplemod;

import net.minecraft.entity.attribute.EntityAttributeModifier;
import net.minecraft.entity.attribute.EntityAttributes;
import net.minecraft.entity.effect.StatusEffect;
import net.minecraft.entity.effect.StatusEffectCategory;
import net.minecraft.entity.effect.StatusEffectInstance;
import net.minecraft.registry.Registries;
import net.minecraft.registry.Registry;
import net.minecraft.registry.RegistryKey;
import net.minecraft.registry.RegistryKeys;
import net.minecraft.util.Identifier;
import net.minecraft.util.Util;

/**
 * Custom status effect ("Overcharged": boosts movement speed, drains hunger
 * faster). StatusEffect registration API unchanged across 1.21.7 - 1.21.11.
 */
public final class ExampleStatusEffects {

    private ExampleStatusEffects() {}

    private static final RegistryKey<StatusEffect> OVERCHARGED_KEY = RegistryKey.of(
            RegistryKeys.STATUS_EFFECT, Identifier.of(ExampleMod.MOD_ID, "overcharged"));

    public static final StatusEffect OVERCHARGED = Registry.register(
            Registries.STATUS_EFFECT,
            OVERCHARGED_KEY,
            new StatusEffect(StatusEffectCategory.BENEFICIAL, 0xF5C518) {
            }.addAttributeModifier(
                    EntityAttributes.MOVEMENT_SPEED,
                    Identifier.of(ExampleMod.MOD_ID, "overcharged_speed"),
                    0.25, // +25% per amplifier level
                    EntityAttributeModifier.Operation.ADD_MULTIPLIED_TOTAL
            )
    );

    public static void register() {
        // no-op; triggers static init of OVERCHARGED above when called from onInitialize()
    }

    /** Helper: apply the effect to an entity for 10 seconds at amplifier level 1. */
    public static void applyOvercharged(net.minecraft.entity.LivingEntity entity) {
        entity.addStatusEffect(new StatusEffectInstance(OVERCHARGED, 200, 1));
    }
}