Combo result
Target opponent loses the game. Near-infinite damage. Prerequisites
All permanents on the battlefield. Curse of Bloodletting attached to an opponent with an even life total. Heartless Hidetsugu does not have summoning sickness.
Aetherflux Reservoir + Purity + Curse of Bloodletting
Combo result
Infinite damage. Infinite lifegain. Infinite lifegain triggers. Prerequisites
All permanents on the battlefield. Your life total is at least 51. Curse of Bloodletting enchanting you.