Mana Echoes + Whitemane Lion + Stonework Packbeast

Mana Echoes

Whitemane Lion

Stonework Packbeast

How it works

1. Cast Whitemane Lion by paying 1.
2. When Whitemane Lion enters the battlefield, it triggers itself and Mana Echoes.
3. Resolve the Mana Echoes trigger, adding at least CCCC.
4. Resolve Whitemane Lion's trigger, returning itself from the battlefield to your hand.
5. Activate Stonework Packbeast by paying 2, adding .
6. Repeat any number of times.
7. Once you have infinite colorless mana, you may activate Stonework Packbeast any number of times.