To get the hard badge, make sure your first three adventurers are mages, rogues, paladins, or a mix of them. The items that give HP boots per level and ressurect at death are some of the best items in the game. Put the rest into damage percent, or failing that regular/magic damage. If you're about to die, stop. Don't lose those first adventurers, they are your gods of dungeon killing. Keep alive if it's good!
@freaky20 I used lots of fire defence and kept the golem's element at fire, but that might just be my trick. Make sure you pack a lot of resistance in a single school, and use abilities that will damage him once (a nice trick is to just use attack, attack, attack to keep him attacking with the same element.) Use as many debuffs as possible, and pack coffee. Also, run Natz and go heal-tastic. (I personally used Lance and Anna too, for running medipack and renew.) He is a tough fight, so make sure you've used all your permanent buffs. Also, have at least 2 sets of coffee ready... just in case.