Retreat to Coralhelm + Llanowar Scout + Guildless Commons

Retreat to Coralhelm

Llanowar Scout

Guildless Commons

How it works

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