Retreat to Coralhelm, Sakura-Tribe Scout, and Boros Garrison

Prerequisites

• Retreat to Coralhelm on the battlefield
• Sakura-Tribe Scout on the battlefield
• Boros Garrison in hand
• Sakura-Tribe Scout does not have summoning sickness

Steps

1. Activate Sakura-Tribe Scout by tapping it, putting Boros Garrison from your hand onto the battlefield
2. Boros Garrison enters the battlefield, triggering itself and Retreat to Coralhelm
3. Resolve the Boros Garrison trigger, returning itself from the battlefield to your hand
4. Resolve the Retreat to Coralhelm trigger, untapping Sakura-Tribe Scout
5. Repeat

Results

• Infinite landfall triggers