Malcolm, Keen-Eyed Navigator, Reckless Fireweaver, and Amoeboid Changeling

Prerequisites

• Malcolm, Keen-Eyed Navigator on the battlefield
• Reckless Fireweaver on the battlefield
• Amoeboid Changeling on the battlefield

Steps

1. Activate Amoeboid Changeling by tapping, targeting Reckless Fireweaver
2. Cause an artifact to enter the battlefield under your control
3. Reckless Fireweaver triggers, dealing 1 damage to each opponent
4. Malcolm triggers, creating a Treasure token for each opponent dealt damage this way
5. The Treasures enter the battlefield, triggering Reckless Fireweaver that many times
6. Resolve the first Reckless Fireweaver trigger, dealing 1 damage to each opponent
7. Repeat from step 4

Results

• Infinite colored mana
• Infinite damage
• Infinite Treasure tokens