EntityWitherSkeleton.java

import net.minecraft.entity.monster.EntitySkeleton;
import net.minecraft.world.World;

public class EntityWitherSkeleton extends EntitySkeleton {

	public EntityWitherSkeleton(World p_i1741_1_) {
		super(p_i1741_1_);
		this.setSkeletonType(1);
	}
}
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EntityRegistry.addSpawn(EntityWitherSkeleton.class, 100, 10, 100, EnumCreatureType.monster, BiomeGenBase.forest);