Activate Phyrexian Altar by sacrificing Greedy Freebooter, adding 1.
When Greedy Freebooter dies, it and Rakdos trigger.
Resolve the Greedy Freebooter trigger, creating a Treasure token and causing you to scry 1.
Activate the Treasure by tapping and sacrificing it, adding .
Holding priority, activate Haunted Crossroads by paying , putting Greedy Freebooter from your graveyard onto the top of your library.
Resolve the Rakdos trigger, exiling Greedy Freedbooter from the top of your library with the ability to cast it until your next turn.
Cast Greedy Freebooter from exile by paying 1.
Repeat.
This elegant loop transforms the humble Greedy Freebooter into an endless engine of sacrifice and discovery, all fueled by the mana-generating versatility of Phyrexian Altar. As the Freebooter repeatedly meets its end, Haunted Crossroads steps in to rescue it from the graveyard straight to the top of your library for a mere black mana. Meanwhile, Rakdos, the Muscle harnesses those very sacrifices to continually exile the Freebooter from your library, granting you free rein to cast it over and over again.