Patron of the Moon + Rakdos Carnarium + Horizon Explorer

Patron of the Moon

Rakdos Carnarium

Horizon Explorer

How it works

1. Pay 1 to activate Patron of the Moon, putting Rakdos Carnarium from your hand onto the battlefield untapped due to Horizon Explorer.
2. When Rakdos Carnarium enters, it triggers.
3. Activate Rakdos Carnarium by tapping it, adding two mana.
4. Resolve Rakdos Carnarium's triggered ability, returning it from the battlefield to your hand.
5. Repeat.