Clock of Omens + Mycosynth Lattice + Shrieking Drake + Grinding Station

Clock of Omens

Mycosynth Lattice

Shrieking Drake

Grinding Station

How it works

1. Activate a permanent you control by tapping it, adding at least 2.
2. Cast Shrieking Drake by paying 1.
3. Shrieking Drake enters the battlefield, triggering itself and Grinding Station.
4. Resolve the Grinding Station trigger, untapping it.
5. Activate Clock of Omens by tapping Grinding Station and Shrieking Drake, untapping the mana-producing permanent.
6. Resolve the Shrieking Drake trigger from step 3, returning itself from the battlefield to your hand.
7. Repeat.