In the Plain of Fire you will fight an extremely difficult Boss. An easy way to defeat him requires two players. Have one player hit the dragon so it will chase him or her. Have the player who hit the dragon stay a few inches away from it. The dragon will then breath fire on that player. Have the other player kill the dragon. The dragon will not turn on the other player. You should have a weaker player kill the dragon so that they get more experience. You can also try using the player with the best melee damage, although a single player can do this trick as well. You must wait until the Dragon begins to take in air. When this happens, attack the dragon's side. Never attack the face or back of the dragon, as it has a powerful bite and tail wipe attack.