MTG >Combos >Mairsil, the Pretender +Workhorse +Blood Vassal +Endling +

Exile all cards with Mairsil Pay one black mana to give Undying to Mairsil Sacrifice Mairsil to add one black mana Undying's ability will trigger, return Mairsil to the battlefield Remove a +1/+1 Counter from Mairsil to add one mana. Repeat the process for infinite mana.