Hemokinesis

Hemokinesis is a 1-Energy Ironclad attack that costs 2 HP and deals 15 damage (20 upgraded). At 15 damage for 1 Energy, it's one of the most damage-efficient cards in the game. The 2 HP cost is a real drawback — in a long run, paying life repeatedly adds up — but the sheer damage output often justifies it, especially against bosses and Elites where speed matters more than HP efficiency.

Hemokinesis works well in tandem with Reaper, which heals based on damage dealt, potentially offsetting the HP cost. It also synergizes with Blood for Blood by triggering its damage-taken reduction. In HP-sustaining builds or runs where you have enough max HP to absorb the costs, Hemokinesis is a high-priority offensive card. The upgrade to 20 damage makes it a consistent combat-shortener.