The best use for Royal Stars is training on Modified Gnarlhounds. The only other option for a paladin to train here is Flaming, Flash, or Shiver arrows which you have to replace every 100 attacks because that is all you can hold in arrow slot. With the Royal Stars they also do fire damage so it allows you to afk, the Modified Gnarlhound will live longer because the damage is lower, and you don't have to refill ammo as often.