Myr Welder, High Alert, and Prismatic Geoscope

Prerequisites

• Myr Welder on the battlefield
• High Alert on the battlefield
• Prismatic Geoscope in exile

Steps

1. Activate Myr Welder using Prismatic Geoscope's ability by tapping it, adding
2. Activate High Alert by paying , untapping Myr Welder
3. Repeat

Results

• Infinite colored mana
• Infinite untap of creatures you control
• Infinite mana creatures you control can produce