The crystal cave battle from "Avatar: The Last Airbender" — that pits Aang and Katara against Azula and Zuko — is one of the best fight sequences of the series. It brilliantly incorporates the philosophy of the three laws of magic, which are guidelines for writing compelling magic systems from fantasy writer Brandon Sanderson. The battle of the crystal cave exemplifies how a well-written magic system can create exceptional storytelling. The scene also does a masterful job of using the fight to reveal character, using the action of the combatants to tell the audience more about each character.