Melira, Sylvok Outcast + Altar of Dementia + Lingering Tormentor

Melira, Sylvok Outcast

Altar of Dementia

Lingering Tormentor

How it works

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

This clever loop turns an ordinary persist creature into a devastating milling engine. When you sacrifice Lingering Tormentor to Altar of Dementia, its persist ability would normally bring it back with a -1/-1 counter, but Melira, Sylvok Outcast's static ability steps in to prevent that counter from ever being placed. Because Lingering Tormentor returns completely clean, you can immediately sacrifice it again to mill your opponent's entire library away.