Definitely 3-13. The storyline right before this chapter (on first time) is really unexpected, and then trying to defeat the GM with your severely under leveled DB peeps is a doozie. When the rest of the GM appeared on like turn 11 of 12 (or something like that), I think I nearly had a heart attack.

Besides, the concept of attacking your own characters is pretty h4x if you ask me.

Try to pick a better chapter. I DARE YOU.

By memory, I'd have to say the chapter you fight Dheginsea. F-whatever.
Dragons + blessed bolting tome/dragonfoe+crossbow = FUCK YES

That's just the one that sticks in my mind. It's been a while since I ran through since I always get bored with part 2.

Any and all of the defend chapters, particularly the ones in part 3.