/**
  * Handles mob spawning.<br>
  * Checks if an arena allows mob spawning before letting a mob spawn inside it.
  */
 @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
 public void onCreatureSpawn(CreatureSpawnEvent event) {
   if (event.getSpawnReason() == SpawnReason.NATURAL) {
     Arena arena = ultimateGames.getArenaManager().getLocationArena(event.getLocation());
     if (arena != null && !arena.allowMobSpawning()) {
       event.setCancelled(true);
     }
   }
 }