Master Transmuter + Sewer-veillance Cam + Grim Monolith + Agatha's Soul Cauldron

Master Transmuter

Sewer-veillance Cam

Grim Monolith

Agatha's Soul Cauldron

How it works

1. Activate Grim Monolith by tapping it, adding at least two mana which you can spend to activate Master Transmuter due to Agatha's Soul Cauldron.
2. Activate Master Transmuter by paying , tapping it, and returning Grim Monolith from the battlefield to your hand, putting Sewer-veillance Cam from your hand onto the battlefield.
3. When Sewer-veillance Cam enters, it triggers, allowing you to untap Master Transmuter.
4. Activate Master Transmuter by paying , tapping it, and returning Sewer-veillance Cam from the battlefield to your hand, putting Grim Monolith from your hand onto the vattlefield.
5. When Sewer-veillance Cam leaves the battlefield, it triggers, allowing you to untap Master Transmuter.
6. Repeat.