Mortuary + Blasting Station + Bolas's Citadel + Kobolds of Kher Keep

Mortuary

Blasting Station

Bolas's Citadel

Kobolds of Kher Keep

How it works

1. Activate Blasting Station by tapping it and sacrificing Kobolds of Kher Keep
2. When Kobolds of Kher Keep dies, Mortuary triggers, putting Kobolds of Kher Keep from your graveyard onto the top of your library.
3. Resolve the Blasting Station ability.
4. Cast Kobolds of Kher Keep from the top of your library by paying 0 life.
5. When Kobolds of Kher Keep enters, Blasting Station triggers, untapping Blasting Station.
6. Repeat.

This loop relies on the zero-mana cost of Kobolds of Kher Keep to keep the machinery turning without draining your life total through Bolas's Citadel. By sacrificing the creature to Blasting Station, you trigger Mortuary to neatly recycle it straight to the top of your library where Bolas's Citadel lets you recast it for free. Each re-entry untaps Blasting Station via its own triggered ability, allowing you to repeat the cycle endlessly to deal infinite damage to your opponents.