Moritte of the Frost + River Kelpie + Altar of Dementia

Moritte of the Frost

River Kelpie

Altar of Dementia

How it works

1. Activate Altar of Dementia by sacrificing Moritte of the Frost.
2. When Moritte of the Frost dies, its persist ability triggers, returning it from your graveyard to the battlefield as a copy of River Kelpie with two additional +1/+1 counters on it and a -1/-1 counter on it.
3. Remove one +1/+1 counter and one -1/-1 counter from Moritte of the Frost as a state-based action.
4. When Moritte of the Frost enters the battlefield, it and River Kelpie's first ability triggers, causing you to draw two cards.
5. Resolve the Altar of Dementia ability from step 1, milling target player a number of cards equal to Moritte of the Frost's power at the time of activation.
6. Repeat.

This ingenious loop revolves around Moritte of the Frost entering the battlefield as a copy of River Kelpie, cleverly bypassing the usual limits of the persist mechanic by leveraging its unique replacement effect to drop with extra +1/+1 counters. When you feed this copied Moritte of the Frost to Altar of Dementia, it hits the graveyard and immediately triggers its newly acquired persist ability to return to the battlefield. The presence of the original River Kelpie—combined with the copy entering—turns each iteration into a card-drawing engine, while Altar of Dementia mills your opponents (or yourself) down to the last card.