Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Ashnod's Altar + Cultivator of Blades

Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight

Ashnod's Altar

Cultivator of Blades

How it works

1. Activate Ashnod's Altar by sacrificing Cultivator of Blades.
2. When Cultivator of Blades dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When Cultivator of Blades enters, its fabricate ability triggers, putting a +1/+1 counter on it.
4. Repeat.

This loop is a masterclass in recycling, powered by Isilu, Carrier of Twilight's passive ability granting persist to your other nontoken creatures so they refuse to stay in the graveyard. When you sacrifice Cultivator of Blades to Ashnod's Altar for a pair of colorless mana, its persist ability brings it straight back with a -1/-1 counter, but the enter-the-battlefield trigger from its fabricate ability places a +1/+1 counter on it. Thanks to the rules of Magic, state-based actions immediately cause these opposing counters to annihilate each other, leaving Cultivator of Blades clean and ready to feed back into Ashnod's Altar all over again. (Though Eirdu, Carrier of Dawn shares this card's backside, it is Isilu, Carrier of Twilight that holds the key to the entire engine by keeping the recursion going indefinitely!)