"Balthazar threatens the Crystal Desert and adjoining kingdom of Elona with his Forged legions. Explore vast new maps filled with magic-drenched desert plains, ancient temples and ruins, and beautiful oases. Uncover the secrets of Tyria's history, and discover the fate of the Elonian people after years of silence."
Path of Fire is getting a revamp to the mount system, elite specializations as well as more rewards, bounties and guild options and all new zones. I imagine this expansion will send a flood of old players back to the game so if you have yet to check it out and are interested now seems like a good time.