Beat slime its in 2 tries with Human Monk, Conversion Seal and 225% conversion item, xtra subdungeon, scout altar, fireball, 50 gold, small shield, str, schaden and whoopaz potions.
Converted the seal, got IMAWAL from EM, used it on high lvl enemies, leveled up regen fighting higher meatmen (one per lvl up if possible, to avoid having poison on meatmen), started fighting supermeatman at 6, used whoopaz, leveled up at least once mid fight, switched to jehora, killed more stuff to gain piety, desecrated EM, fireballed the goo to death (one mid fight lvl up, one more from jehora, used pactmaker to get more piety to try for a last chance but failed).
I think I had some potions left over.
This is the second stuidly hard quest i've finished with a lockered 225% conversion and seal thingy. Not sure how i would've done it otherwise, and since the quest was made while the monk was god tier, and he is crap tier now, I'm not sure if it was ment to be that helpfull.