Quote Originally Posted by Zzyzxx71 View Post
There's nothing suckier than getting to him the first time and having him just walk through the portal because you ran out of time. Once you engage him if the timer runs out he WILL walk through the portal with you beating on his ass.
If I remember correctly, you can still hurt him while he is walking towards the portal. So pull him away from his portal at the start of the fight to buy some extra time.