[SixOfSpades]

Due to a nastiness of the Tower, once you breach the 2nd underground level, you're in it for the long haul: No trips back to town to sell stuff, or even going to the ground floor to Rest. Once you use the Wardstones to open the doors, they will close again in about 8 hours, and there's no known way of opening them again. I wish this irritating fact was packaged with the game, but sadly it isn't.

I find it ironic that they put this battle in terms of chess, a game where neither player has any material advantage whatsoever and must win through strategy. In Durlag's Tower, the material odds are hopelessly against you, so the only way to win is to not give the other team a chance at all. In short, if they have the opportunity to attack you before you've killed at least a third of their team, you're doing it wrong.

"Backtrack to re-up your party?" If that means, "Can I take my party upstairs to Rest and heal?" then no, you can't. If it means, "Once I've gotten to the chess game, can we go back upstairs?" then no, you still can't. As soon as you hit the chess game, the only way back up is to keep going down.