Havengul Lich + Grimgrin, Corpse-Born + Cryptolith Rite + Diregraf Colossus

Havengul Lich

Grimgrin, Corpse-Born

Cryptolith Rite

Diregraf Colossus

How it works

1. Activate Grimgrin's ability from Cryptolith Rite by tapping Grimgrin, adding one mana.
2. Activate Grimgrin by sacrificing the zombie castable for one mana, untapping Grimgrin and putting a +1/+1 counter on it.
3. Activate Grimgrin's ability from Cryptolith Rite by tapping Grimgrin, adding one mana.
4. Activate Havengul Lich by paying 1, allowing you to cast the zombie castable for one mana from your graveyard this turn.
5. Cast that zombie spell from your graveyard by paying it mana cost.
6. When you cast that zombie or when it enters, Diregraf Colossus triggers, creating a creature token.
7. Activate Grimgrin by sacrificing the creature token, untapping Grimgrin and putting a +1/+1 counter on it.
8. Repeat.