The list I gave you is in no particular order. Here's imo list of areas from hardest to easiest. You'll need GM Protection from Magic for Blood Titans, Ancient Wyverns, Minotaur Lords, and Robert The Wise/Tolberti. The Devils in Lands of the Giant can cast Meteor Shower. If your having problems with anything work on your Cleric getting GM Body and Light magic if they don't have it yet.Land of the Giants
Tunnel of EOFOL
Maze
Nighon
Thunderfist Mountain
Pit
Wine Cellar
Watchtower 6
Avlee
Clanker's Lab
Markham's Manor and Mercenary Guild
Deyja
Bracada Desert
Erathia
Evermorn Island
Barrowdowns
Harmondale