Marvin, Murderous Mimic, Simic Ragworm, and Deathbloom Ritualist

Prerequisites

• Marvin, Murderous Mimic on the battlefield
• Simic Ragworm on the battlefield
• Deathbloom Ritualist on the battlefield

Steps

1. Activate Marvin using Deathbloom Ritualist's ability by tapping it, adding at least
2. Activate Marvin using Simic Ragworm's ability by paying , untapping it
3. Repeat

Results

• Infinite colored mana