I actually finished.
Only lost 3 heroes (Lepus, Rigard x2; technically lost Gravemaker on the last floor but it didn’t matter anymore lol) with many more having 1 curse, but that’s only because I burned up a shed load of tornadoes to achieve that (probably used about 30 throughout).
Well glad it’s done, timestops and timefreezes became absolutely invaluable from floor 45 onwards, as Cobalt and Onyx could one shot your whole team if you’re not careful. The four items I carried with me from floor 40-48 minor mana pots, tornadoes, hurricanes, and timestops. For floors 49 and 50, since I could afford to lose every hero, I swapped out tornadoes and hurricanes for timefreezes and panaceas. Very fortunately only had to use one timefreeze on the last floor, and didn’t need to touch the panaceas.
The one blessing I found to be a significant game changer was the 5% mana generation. I stacked 5 of those for a ludicrous +25% mana boost for the last 5 floors. The net effect is with a lv 11 mana troop, fast heroes become very fast, and with maxed costume only a lv 1 mana troop is required. A very fast Hansel+18 - even if his effect only lasts one turn now - is pretty much a living timestop.
The second most useful blessing actually turned out to be the minions, I stacked 3 of those in the end and having that +15% HP every 5 turns very nicely countered the constant poison floor DoT.