Fiend Hunter + Phyrexian Delver + Trostani, Selesnya's Voice + Viscera Seer

Fiend Hunter

Phyrexian Delver

Trostani, Selesnya's Voice

Viscera Seer

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 Viscera Seer 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 Viscera Seer abilities, causing you to scry 1 infinite times.

This elegant loop relies on the continuous recycling of Fiend Hunter and Phyrexian Delver between the battlefield and the graveyard, with Viscera Seer acting as the sacrificial outlet that breaks the loop and triggers the descent. As each creature repeatedly enters the battlefield, Trostani, Selesnya's Voice observes the commotion to pad your life total while you churn through your entire library via infinite scry activations.