Appa, Steadfast Guardian + Eternal Scourge + Ashnod's Altar + Mimic Vat

Appa, Steadfast Guardian

Eternal Scourge

Ashnod's Altar

Mimic Vat

How it works

1. Cast Eternal Scourge from exile by paying 3.
2. Appa's second ability triggers, creating a 1/1 Ally creature token.
3. Activate Ashnod's Altar twice by sacrificing Eternal Scourge and the Ally, adding CCCC.
4. When Eternal Scourge dies, Mimic Vat triggers, exiling Eternal Scourge from your graveyard.
5. Repeat.

This loop relies on Eternal Scourge’s intrinsic ability to be continuously recast from exile, providing the recurring fodder needed to keep the engine running. By channeling that fuel through Ashnod's Altar, you sacrifice both the Scourge and the 1/1 tokens generated by Appa, Steadfast Guardian—which triggers whenever you cast a spell from exile—to continuously net colorless mana. Meanwhile, Mimic Vat acts as an essential safety net in your graveyard, ready to imprint the Scourge if needed, though the primary casting loop simply feeds right back into Appa's airbending synergy.