Retreat to Coralhelm, Storm Cauldron, and PuPu UFO

Prerequisites

• Retreat to Coralhelm on the battlefield
• Storm Cauldron on the battlefield
• PuPu UFO on the battlefield

Steps

1. Activate PuPu UFO by tapping it, putting a basic land from your hand onto the battlefield
2. When the land enters the battlefield, Retreat to Coralhelm triggers, untapping PuPu UFO
3. Activate the basic land by tapping it, adding
4. Storm Cauldron triggers, returning the basic land from your battlefield to your hand
5. Repeat

Results

• Infinite landfall triggers
• Infinite mana basic lands you control can produce