Mana Echoes, Whitemane Lion, and Stonework Packbeast

Prerequisites

• Mana Echoes on the battlefield
• Whitemane Lion in hand
• Stonework Packbeast on the battlefield
• You control at least three Cat creatures
• available

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

• Infinite colored mana
• Infinite colorless mana
• Infinite ETB
• Infinite LTB
• Infinite storm count