furthest I got was to a boss just before the top of act 3 (giant head) got him to around 100 health from 450 and his randomly changing damage intent switched from 2x10 to 45 on my last card of a turn where i had a hand of mostly attack cards and he just obliterated me.
Oops...
Collectible card games + rogue likes = no sleep.
Also very much enjoyed Meteorfall: Journeys