Make sure you stay as close to your opponent as possible, and keep circling around him. The Commander isn't that much trickier than your earlier battle against the First Warden, but you'll need your wits about you nevertheless. If you do so after the boss fight is over, however, you'll be able to do a character respec instead. Before you begin this fight, be aware that you can interact with the statues on the left-hand side of the battle area to grab their weapons if you've got the Shard of the Heroes on you.
