Primal Prayers + Decoction Module + Shrieking Drake

Primal Prayers

Decoction Module

Shrieking Drake

How it works

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