Rakdos, the Muscle + Priest of Gix + Haunted Crossroads + Sifter of Skulls + Phantom Train

Rakdos, the Muscle

Priest of Gix

Haunted Crossroads

Sifter of Skulls

Phantom Train

How it works

1. Activate Phantom Train by sacrificing Priest of Gix.
2. When Priest of Gix dies, Sifter of Skulls and Rakdos trigger.
3. Resolve the Sifter of Skulls trigger, creating a 1/1 Eldrazi Scion creature token.
4. Holding priority, activate Haunted Crossroads by paying , putting Priest of Gix from your graveyard onto the top of your library.
5. Resolve the Rakdos trigger, causing you to exile the top three cards of your library with the ability to play them until your next end step.
6. Resolve the Phantom Train ability from step 1, putting a +1/+1 counter on it.
7. Activate the Eldrazi Scion by sacrificing it, adding C.
8. Cast Priest of Gix from exile by paying 3.
9. When Priest of Gix enters the battlefield, it triggers, adding .
10. Repeat.

This loop uses Phantom Train as an engine to continuously sacrifice Priest of Gix, which generates a flood of black mana each time it re-enters the battlefield. Sifter of Skulls ensures that every sacrifice replaces itself with an Eldrazi Scion, which can be sacrificed for the colorless mana needed alongside Haunted Crossroads to recycle the Priest right back to the top of your library. Meanwhile, Rakdos, the Muscle capitalizes on the constant stream of sacrificed creatures by exiling your entire library card by card, letting you freely cast and play your entire deck using any type of mana.