Havengul Lich + Grimgrin, Corpse-Born + Blessed Sanctuary + Ashaya, Soul of the Wild

Havengul Lich

Grimgrin, Corpse-Born

Blessed Sanctuary

Ashaya, Soul of the Wild

How it works

1. Activate Grimgrin's ability from Ashaya by tapping Grimgrin, adding one mana.
2. Activate Grimgrin by sacrificing the creature castable for one mana, untapping Grimgrin and putting a +1/+1 counter on it.
3. Activate Grimgrin's ability from Ashaya by tapping Grimgrin, adding one mana.
4. Activate Havengul Lich by paying 1, allowing you to cast the creature castable for one mana from your graveyard this turn.
5. Cast that creature spell from your graveyard by paying it mana cost.
6. When you cast that creature or when it enters, Blessed Sanctuary 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.

This intricate loop transforms your graveyard into an endless engine of growth and token generation. Ashaya, Soul of the Wild quietly lays the foundation by turning all your nontoken creatures into Forests, granting Grimgrin, Corpse-Born the innate ability to tap for mana just like any land. With Grimgrin tapping itself for mana and sacrificing creatures to untap and grow, Havengul Lich steps in to repeatedly fund and cast a creature right back out of your graveyard. Every single time that creature enters the battlefield, Blessed Sanctuary triggers to conjure a fresh Unicorn token, providing a steady stream of fodder to keep Grimgrin's sacrifices rolling indefinitely.