Clock of Omens + Mycosynth Lattice + Shrieking Drake + Battered Golem

Clock of Omens

Mycosynth Lattice

Shrieking Drake

Battered Golem

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 Battered Golem.
4. Resolve the Battered Golem trigger, untapping it.
5. Activate Clock of Omens by tapping Battered Golem 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.