Ashnod's Altar + Nim Deathmantle + Teysa Karlov + Myr Moonvessel

Ashnod's Altar

Nim Deathmantle

Teysa Karlov

Myr Moonvessel

How it works

1. Activate Ashnod's Altar by sacrificing Myr Moonvessel, adding CC.
2. When Myr Moonvessel dies, it and Nim Deathmantle triggers twice.
3. Resolve both Myr Moonvessel triggers, adding CC.
4. Resolve the first Nim Deathmantle trigger, choosing not to pay.
5. Resolve the second Nim Deathmantle trigger, causing you to pay 4 to return Myr Moonvessel from your graveyard to the battlefield, and attach Nim Deathmantle to it.
6. Repeat.

This delightful loop relies on Teysa Karlov doubling the death-triggered abilities of your permanents, turning a single sacrifice into a cascade of value. When you sacrifice Myr Moonvessel to Ashnod's Altar, you generate colorless mana and trigger both the Myr's own mana-producing death ability and Nim Deathmantle's resurrection trigger twice over. With the extra mana provided by the Altar and the Moonvessel itself, you easily afford the four-mana cost to return the Myr to the battlefield via the Deathmantle, leaving you with an engine that endlessly recycles your creatures for infinite sacrifices, triggers, and colorless mana.