Huh, I actually hadn't thought of how useful the fire heart might be. As much as I've been using glyphs, I have ignored that as well as the dragon soul in most of my attempts for either being too expensive or not having the right glyphs to use with them.
EDIT: Just had a run that likely had all of the elements required for success - Halpmeh and Getindare, early Taurog + GG + Dracul, midas gloves + platemail + troll heart + witchalok pendant (resists were slow with a late PM), and back-to-back Golden Statue and Illusion and an early Bridge Troll on top of no fully revealed floor and an early first strike floor. What went wrong, you might ask? I started off in Taurog and planned on picking up the helm and armor before hopping into GG for the tower phase, but only grabbed the armor before I filled up my inventory with shop items and glyphs. No worries, I could convert the troll heart and pick up the helm then hop into GG. 3 seconds later, I realized that I had converted into GG without taking the helm. This was annoying, but there was lots to convert and I could easily meet the conversion requirement. I go back to Taurog, grab the helm, and then realize that I would have to kill all of my remaining popcorn to get back to 50 piety for going back to GG. I wanted to use the resist scroll, so I knew I needed 3 monsters left to clear the curses, so I ditched Halpmeh and left 3 first strikers for curse clearing and the extra body pact resists. At this point, I was back in GG, but I was already level 10 so I earned little to no piety from the 4-5 level ups I had afterwards. The rest of the tower was a slow downward spiral until I completely crashed at the 9th floor with no resources left to beat the elite dragonspawn and a remaining warlock. Had I properly managed my conversions, I would have had 35% both resists by the 3rd floor on top of platemail, and would have been able to get not only to Horatio but at least a few thousand damage in if not an outright win.
Still sour about that loss.