Defiler of Faith + The Immortal Sun + Auriok Champion + Whitemane Lion

Defiler of Faith

The Immortal Sun

Auriok Champion

Whitemane Lion

How it works

1. Cast Whitemane Lion by paying 0 and 2 life due to Defiler of Faith and The Immortal Sun.
2. Defiler of Faith triggers, creating a 1/1 Soldier creature token.
3. When the Soldier enters, Auriok Champion triggers, causing you to gain life.
4. Resolve Whitemane Lion. When it enters, it and Auriok Champion trigger.
5. Resolve the Whitemane Lion trigger, returning it from the battlefield to your hand.
6. Resolve the Auriok Champion trigger, causing you to gain life.
7. Repeat.

This loop relies on a brilliant cost-reduction stacking trick: with The Immortal Sun shaving {1} off your spells and Defiler of Faith letting you trade 2 life to reduce white mana costs by {W}, Whitemane Lion becomes entirely free to cast at zero mana. Once the Lion hits the battlefield, its own entry trigger forces you to bounce it right back to your hand so you can repeat the process indefinitely. Meanwhile, Defiler of Faith happily triggers on every single cast to flood your board with an endless army of 1/1 Soldier tokens. As those tokens enter, Auriok Champion triggers every single time to generate an unstoppable stream of infinite life, completing a self-sustaining engine of creation and resilience.