Havengul Lich + Grimgrin, Corpse-Born + Relic of Legends + Fumulus, the Infestation

Havengul Lich

Grimgrin, Corpse-Born

Relic of Legends

Fumulus, the Infestation

How it works

1. Activate Relic of Legends's last ability 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. When that creature dies, Fumulus triggers, creating a creature token or a token that adds mana.
4. If you created a creature token, repeat steps 1 and 2 to sacrifice that token and add an additional mana.
5. If you created a token that adds mana, instead activate that token to add mana.
6. Activate Havengul Lich by paying 1, allowing you to cast the sacrificed creature from your graveyard this turn.
7. Cast that creature from your graveyard by paying one mana.
8. Repeat.

This elegant loop centers on Grimgrin, Corpse-Born, who uses Relic of Legends to tap for mana before being untap-fueled by sacrificing a creature. As that sacrifice occurs, Fumulus, the Infestation triggers to generate a fresh Insect token to keep the momentum going. To close the circuit, Havengul Lich steps in by paying {1} to continuously recast that sacrificed creature from your graveyard, ensuring your engine never runs dry of sacrificial fodder.