Sister Hospitaller + Fiend Hunter + Phantom Train

Sister Hospitaller

Fiend Hunter

Phantom Train

How it works

1. Cast Fiend Hunter by paying its mana cost.
2. When Fiend Hunter enters, its first ability triggers, exiling Sister Hospitaller.
3. Activate Phantom Train by sacrificing Fiend Hunter.
4. When Fiend Hunter dies, its second ability triggers, returning Sister Hospitaller from exile to the battlefield.
5. When Sister Hospitaller enters, it triggers, returning Fiend Hunter from your graveyard to the battlefield.
6. When Fiend Hunter enters, its first ability triggers, exiling Sister Hospitaller.
7. Resolve the Phantom Train ability.
8. Repeat from step 3.

This loop sets up an endless cycle of sacrifice and resurrection by bouncing Sister Hospitaller and Fiend Hunter back and forth between the battlefield, graveyard, and exile. As Phantom Train acts as the permanent sacrificial outlet that turns the Hunter into a temporary Spirit artifact creature, Sister Hospitaller continually swoops in upon entering to pull Fiend Hunter right back from the graveyard. This cascading engine generates infinite death triggers, life gain, and creature leaves-the-battlefield events while pumping up your board with boundless +1/+1 counters.