Retreat to Coralhelm, Llanowar Scout, and Rakdos Carnarium

Prerequisites

• Retreat to Coralhelm on the battlefield
• Llanowar Scout on the battlefield
• Rakdos Carnarium in hand
• Llanowar Scout does not have summoning sickness

Steps

1. Activate Llanowar Scout by tapping it, putting Rakdos Carnarium from your hand onto the battlefield
2. Rakdos Carnarium enters the battlefield, triggering itself and Retreat to Coralhelm
3. Resolve the Rakdos Carnarium trigger, returning itself from the battlefield to your hand
4. Resolve the Retreat to Coralhelm trigger, untapping Llanowar Scout
5. Repeat

Results

• Infinite landfall triggers