Jegantha, the Wellspring, High Alert, and Zirda, the Dawnwaker

Prerequisites

• Jegantha, the Wellspring on the battlefield
• High Alert on the battlefield
• Zirda, the Dawnwaker on the battlefield
• Jegantha does not have summoning sickness

Steps

1. Activate Jegantha by tapping it, adding that cannot be spent to pay generic mana costs
2. Activate High Alert by paying , untapping Jegantha
3. Repeat

Results

• Infinite black mana that cannot be spent to pay generic mana costs
• Infinite green mana that cannot be spent to pay generic mana costs
• Infinite red mana that cannot be spent to pay generic mana costs