2 conditions needed for easy win ( thought I'd put it up, since i wished some1 else had )
1. Dwarven Bloodmage ( i tried both human and dwarf, but since I noticed his damage was quite low ... )
Dracul is the patron god of Gaan-Telet. Hands down, no holds barred, finding Dracul regardless
of what class you may be is going to make this level much easier.
Even without Dracul, the Bloodmage is a highly reliable and effective class on this dungeon, and since the Bloodmage makes a great Dracul worshipper that's all the better. Dwarves are certainly solid bloodmages, though personally I prefer the higher damage output of humans.
Also try the Human Paladin for Gaan-Telet. Nothing quite matches up to the combination of the great resistances of the paladin, the reliability of a free HALPMEH glyph, and the high attack power of the human. Paladins also make great followers of Dracul, since they can drink health potions and using their healing glyph without worry of punishment.
Also, welcome to the DD forums.