Retreat to Coralhelm, Trench Behemoth, and Sakura-Tribe Scout

Prerequisites

• Retreat to Coralhelm on the battlefield
• Trench Behemoth on the battlefield
• Sakura-Tribe Scout on the battlefield

Steps

1. Activate Trench Behemoth by returning a land from the battlefield to your hand, untapping Trench Behemoth
2. Activate Sakura-Tribe Scout by tapping it, putting the land from your hand onto the battlefield
3. When the land enters the battlefield, Retreat to Coralhelm triggers, untapping Sakura-Tribe Scout
4. If the land enters untapped and can produce mana, you may activate it by tapping it, adding at least
5. Repeat

Results

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