MTG >Combos >Umbral Mantle +Runed Servitor +Ashnod's Altar +Koll, the Forgemaster +

With Knoll in play, cast Runed Servitor Equip him with Lightning Greaves and sacrifice him with Ashnod's Altar to add two mana Runed Servitor's ability will trigger, each player will draw a card Knoll's ability will trigger, return Runed Servitor to your hand Repeat the process for infinite draw.