Retreat to Coralhelm + Trade Routes + Walking Atlas

Prerequisites

You control a land that enters the battlefield untapped and can tap to produce at least {1}.

Steps

1. Activate the land by tapping it, adding at least {1}.
2. Activate Trade Routes' first ability by paying {1}, returning the land from the battlefield to your hand.
3. Activate Walking Atlas by tapping it, putting the land from your hand onto the battlefield.
4. When the land enters the battlefield, Retreat to Coralhelm triggers, untapping Walking Atlas
5. Repeat.