I found this run interesting because there wasn't one clear strong play and I had to balance several strong things to beat the heart. Overall it was mostly a poison deck (Snecko Skull, Noxious Fumes+, Bouncing Flask+, 2 × Crippling Cloud+) but it notably did not have Catalyst, which made finishing the heart tricky (the fight went all the way to turn 9).
Normally the way you'd make up for a lack of Catalyst is to stack up on Intangible and I did have Wraith Form+ and Incense Burner and at one point I even had 2 Ghost in a Jar potions but had to spend both of them to beat the Mysterious Sphere event (and all I got in return was a Du-Vu Doll; not worth it).
Fortunately, I did have a few other things to help push me over the edge: Singing Bowl helped me start with a high surplus of health, Bronze Scales gave me an extra damage boost, and Ancient Potion let me safely play the Wraith Form+ early.