Primal Prayers + Decoction Module + Dream Stalker

Primal Prayers

Decoction Module

Dream Stalker

How it works

1. Cast Dream Stalker by paying E due to Primal Prayers, if able, or by paying its mana cost.
2. When Dream Stalker enters the battlefield, it and Decoction Module trigger.
3. Resolve the Decoction Module trigger, causing you to get E.
4. Resolve the Dream Stalker trigger, returning it from the battlefield to your hand.
5. Repeat.