The boss, Itsssama, has very high resistances and weakens you, so a low damage character is not recommended. Additionally, you should decide in advance which boss to deal with first; if you rely mostly on physical damage and go after Itsssamna first, you will want to pick up a Fortitude Tonic for after the fight. If you decide to go the spell casting route, it is highly recommended you bring the Piercing Wand to counteract his high resistances. Itsssamna's weakness is his damage - even a L6 rogue can take a hit without dying, so this makes HALPMEH an incredibly valuable glyph. Berserker and Rogue are very good class choices. If you choose a Rogue, you must either find HALPMEH, CYDSTEPP, or an altar to Taurog, because health potions will not last you long enough. If you find a CYDSTEPP glyph, start killing sorcerers, gorgons, and vampires 2-3 levels above you. If you find HALPMEH, it will be monsters 1-2 levels above you. If you find Taurog, only pick up the sword, armor, and possibly shield, as you need the rest of the space for wisp gems. If you go the Berserker route it's Taurog time! Grab the sword, armor, and helmet first converting all glyphs and killing high level sorcerers with your new 65% magic resistance. The boss should be easily outlast-able with any of the 4 tactics.