Retreat to Coralhelm + Guildless Commons + PuPu UFO

Retreat to Coralhelm

Guildless Commons

PuPu UFO

How it works

1. Activate PuPu UFO 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 PuPu UFO.
5. Repeat.