Mister Fantastic, and Unstoppable Plan

Prerequisites

• Mister Fantastic on the battlefield
• Unstoppable Plan on the battlefield

Steps

1. At the beginning of your end step, Unstoppable Plan triggers
2. Holding priority, activate all mana-producing nonland permanents you control by tapping them, adding an amount of mana
3. Activate Mister Fantastic by paying and tapping it, copying Unstoppable Plan's trigger twice
4. Resolve the first copy of Unstoppable Plan's trigger, untapping all nonland permanents you control
5. Holding priority, activate all mana-producing nonland permanents you control by tapping them, adding an amount of mana
6. Resolve the second copy of Unstoppable Plan's trigger, untapping all nonland permanents you control
7. Repeat from step 2

Results

• Infinite mana nonland permanents you control can produce
• Infinite untap of nonland permanents you control