Eirdu, Carrier of Dawn // Isilu, Carrier of Twilight + Altar of Dementia + Scholar of New Horizons

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

Altar of Dementia

Scholar of New Horizons

How it works

1. Activate Altar of Dementia by sacrificing Scholar of New Horizons.
2. When Scholar of New Horizons dies, its persist ability triggers, returning it from your graveyard to the battlefield without a -1/-1 counter on it due to its replacement effect.
3. Resolve the Altar of Dementia ability.
4. Repeat.

This ingenious loop relies on Isilu, Carrier of Twilight—the transformed back side of Eirdu, Carrier of Dawn—granting persist to all your other nontoken creatures, which safely turns Altar of Dementia into a recursive engine. When you sacrifice Scholar of New Horizons to the Altar, its persist ability brings it straight back to the battlefield with a -1/-1 counter; however, Scholar of New Horizons enters with a +1/+1 counter of its own, meaning the two counters immediately cancel each other out as a state-based action. This leaves the Scholar completely clean of counters and ready to be sacrificed over and over again, milling your opponents out completely while generating an endless stream of death, entry, and sacrifice triggers.