Activate Aether Vial by tapping it, putting Pestermite onto the battlefield from your hand.
When Pestermite enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Pestermite trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Deceiver Exarch from the battlefield to your hand.
Activate Aether Vial by tapping it, putting Deceiver Exarch onto the battlefield from your hand.
When Deceiver Exarch enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Deceiver Exarch trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Pestermite from the battlefield to your hand.
Repeat.

Infinite creature ETB

Infinite creature LTB

Aether Vial

Cloudstone Curio

Pestermite

Deceiver Exarch

Activate Aether Vial by tapping it, putting Deceiver Exarch onto the battlefield from your hand.
When Deceiver Exarch enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Deceiver Exarch trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Derevi from the battlefield to your hand.
Activate Aether Vial by tapping it, putting Derevi onto the battlefield from your hand.
When Derevi enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Derevi trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Deceiver Exarch from the battlefield to your hand.
Repeat.

Derevi, Empyrial Tactician

Activate Aether Vial by tapping it, putting Pestermite onto the battlefield from your hand.
When Pestermite enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Pestermite trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Derevi from the battlefield to your hand.
Activate Aether Vial by tapping it, putting Derevi onto the battlefield from your hand.
When Derevi enters the battlefield, it and Cloudstone Curio trigger.
Resolve the Derevi trigger, untapping Aether Vial.
Resolve the Cloudstone Curio trigger, returning Pestermite from the battlefield to your hand.
Repeat.

Combos with "Aether Vial"