Cayth, Famed Mechanist + Altar of Dementia

Cayth, Famed Mechanist

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing the persist creature.
2. When the persist creature dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When the persist creature enters the battlefield, its fabricate ability triggers, putting a +1/+1 counter on it.
4. Resolve the Altar of Dementia ability, causing target player to mill cards equal to the persist creature's power.
5. Repeat.