Retreat to Coralhelm, Cloudstone Curio, and Walking Atlas

Prerequisites

• Retreat to Coralhelm on the battlefield
• Cloudstone Curio on the battlefield
• Walking Atlas on the battlefield

Steps

1. Activate Walking Atlas by tapping it, putting a nonartifact land from your hand onto the battlefield
2. When the land enters the battlefield, Retreat to Coralhelm and Cloudstone Curio trigger
3. Resolve the Retreat to Coralhelm trigger, untapping Walking Atlas
4. Resolve the Cloudstone Curio trigger, returning any other nonartifact land from the battlefield to your hand
5. If the land entered untapped and can produce mana, you may activate it by tapping it, adding at least
6. Repeat

Results

• Infinite landfall triggers
• Infinite mana lands you control that enter the battlefield untapped can produce