Fully upgraded reinforced clubs, fully upgraded light crossbows, great combustion, great fireball. You don't have to grind so much...the game is designed in such a way that you can collect most of the upgrade materials you need, but I did do a bit of farming here and there--nothing crazy. Hardest part by far was Gwyn which was cool because I never had much trouble with him prior to this challenge, so I feel like I finally got the full experience of that fight. Honorable mentions go to the usual suspects, O&S, 4 Kings, Bed of Chaos (seriously, can we just remove this awful encounter from the game). Quelaag was one of my first targets (wanted to max out my pyro flame with Eingyi ASAP) so that was pretty tough since I didn't have a whole lot in the way of offense/defense at that point. Special thanks to Maneater Mildred for tanking it up.