Marvin, Murderous Mimic, Horseshoe Crab, and Bloom Tender

Prerequisites

• Marvin, Murderous Mimic on the battlefield
• Horseshoe Crab on the battlefield
• Bloom Tender on the battlefield

Steps

1. Activate Marvin using Bloom Tender's ability by tapping it, adding at least
2. Activate Marvin using Horseshoe Crab's ability by paying , untapping it
3. Repeat

Results

• Infinite non-blue mana of colors among permanents you control