Requires

Mana Echoes must be on the battlefield. Whitemane Lion must be in hand. Stonework Packbeast must be on the battlefield. You control at least three Cat creatures. Mana needed:

Steps

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

Results