Rakdos, the Muscle + Priest of Gix + Haunted Crossroads + Urza's Incubator + Phantom Train

Rakdos, the Muscle

Priest of Gix

Haunted Crossroads

Urza's Incubator

Phantom Train

How it works

1. Activate Phantom Train by sacrificing Priest of Gix.
2. When Priest of Gix dies, Rakdos triggers.
3. Holding priority, activate Haunted Crossroads by paying , putting Priest of Gix from your graveyard onto the top of your library.
4. 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.
5. Resolve the Phantom Train ability from step 1.
6. Cast Priest of Gix from exile by paying 1.
7. When Priest of Gix enters the battlefield, it triggers, adding .
8. Repeat.

This clever loop lets you turn your graveyard into an engine by cycling Priest of Gix over and over, all fueled by the cost-reduction of Urza's Incubator naming Minions (or Phyrexians, depending on your setup). As you sacrifice the Priest to Phantom Train, Rakdos, the Muscle triggers to exile the top of your library while Haunted Crossroads conveniently puts the Priest right back on top for you to recast. The mana generated by the Priest's entry easily pays for the Crossroads' activation and the discounted recast, leaving you with an ever-growing Phantom Train and a completely exiled library ready to be played.