Nethroi, Apex of Death + Phyrexian Altar + Mitotic Slime + Sparkcaster

Nethroi, Apex of Death

Phyrexian Altar

Mitotic Slime

Sparkcaster

How it works

1. Cast Nethroi either from your hand or from the command zone for its mutate cost by paying 4G/W, putting it under a non-Human creature you control.
2. Nethroi triggers, returning Sparkcaster and Mitotic Slime from your graveyard to the battlefield.
3. When Sparkcaster enters, it triggers, returning Nethroi from the battlefield to your hand.
4. Activate Phyrexian Altar twice by sacrificing Sparkcaster and Mitotic Slime, adding .
5. When Mitotic Slime dies, it triggers, creating two 2/2 Ooze creature tokens.
6. Activate Phyrexian Altar twice by sacrificing the Oozes, adding 1G/W.
7. When the Oozes die, they trigger, creating four 1/1 Ooze creature tokens.
8. Activate Phyrexian Altar three times by sacrificing three Oozes, adding 3.
9. Repeat.

This clever loop turns Nethroi, Apex of Death into a devastating graveyard-recursing engine by leveraging its massive mutate trigger to pull back both Mitotic Slime and Sparkcaster at once. Once on the battlefield, Sparkcaster immediately bounces Nethroi back to your hand so you can recast its mutate cost, while Phyrexian Altar provides the mana needed to sustain the loop by sacrificing creatures for any color. The true brilliance of the chain lies in Mitotic Slime's cascading death triggers: as the Slime and its subsequent 2/2 and 1/1 Ooze tokens perish to the Altar, they generate a surplus of sacrifice fodder and mana.