Fiend Hunter + Phyrexian Delver + Trostani, Selesnya's Voice + Altar of Dementia

Fiend Hunter

Phyrexian Delver

Trostani, Selesnya's Voice

Altar of Dementia

How it works

1. Cast Fiend Hunter by paying 1.
2. Fiend Hunter enters the battlefield, triggering its first ability and Trostani.
3. Resolve the Trostani trigger, causing you to gain life equal to Fiend Hunter's toughness.
4. Resolve the Fiend Hunter trigger, exiling Phyrexian Delver until Fiend Hunter leaves the battlefield.
5. Activate Altar of Dementia by sacrificing Fiend Hunter.
6. Fiend Hunter leaves the battlefield, triggering its second ability, returning Phyrexian Delver from exile to the battlefield.
7. Phyrexian Delver enters the battlefield, triggering itself and Trostani.
8. Resolve the Trostani trigger, causing you to gain life equal to Phyrexian Delver's toughness.
9. Resolve the Phyrexian Delver trigger, returning Fiend Hunter from your graveyard to the battlefield and causing you to lose three life.
10. Repeat from step 2.
11. Resolve all Altar of Dementia abilities, causing target player(s) to mill infinite cards.

This clever loop dances back and forth between the graveyard and the battlefield using Fiend Hunter and Phyrexian Delver to endlessly recur one another, feeding a continuous chain of creature enters-the-battlefield and leaves-the-battlefield events. Every single time Fiend Hunter hits the dirt, Altar of Dementia turns that sudden sacrifice into a relentless stream of targeted milling that strips your opponent's library away entirely. Meanwhile, Trostani, Selesnya's Voice watches the procession and happily rewards all this chaotic recycling with a massive, compounding stream of infinite life.