You can't fall off at the Monestery. There are lots of edges and clifts you can't fall off. And then there is Trynton. Oh, yes.
The first time through I had this problem with the "ropes" "ladders" and "vines". Must have gotten killed about 8 times - without the saplings, thank you.
Feather Fall IS M&M. You don't need it anyplace else but Trynton - so why do we have to keep going back there?
Incedently, in the Monestery I routinely run past Gregor, get ammo, jump down to the lower level till my party is tough enough to take him out. If the party is at health your party should be OK
