@SubscribeEvent
 public void onChunkUnload(ChunkEvent.Unload event) {
   List[] entityLists = event.getChunk().entityLists;
   for (List entityList : entityLists) {
     for (Object thing : entityList) {
       MobPicker.removeMobInstance((Entity) thing);
     }
   }
 }
 @SubscribeEvent
 public void onMobDeath(LivingDeathEvent event) {
   Entity mob = event.entity;
   MobPicker.removeMobInstance(mob);
 }