MTG >Combos >Mikaeus, the Unhallowed +Gravecrawler +Phyrexian Altar +

Sacrifice Gravecrawler with Phyrexian Altar to add one black mana Mikaeus' ability will trigger, return Gravecrawler to the battlefield. Sacrifice Gravecrawler again to add one black mana and cast it from your graveyard for one mana. Repeat the process for infinite mana.