Pitiless Plunderer + Reassembling Skeleton + Delney, Streetwise Lookout + Phantom Train

Pitiless Plunderer

Reassembling Skeleton

Delney, Streetwise Lookout

Phantom Train

How it works

1. Activate Phantom Train by sacrificing Reassembling Skeleton.
2. When Reassembling Skeleton dies, Pitiless Plunderer triggers twice, creating two Treasure tokens.
3. Resolve the Phantom Train ability.
4. Activate the Treasure tokens by tapping and sacrificing them, adding 1.
5. Activate Reassembling Skeleton by paying 1, returning it from your graveyard to the battlefield tapped.
6. Repeat.

This clever loop uses Phantom Train as an outlet to feed our engine, sacrificing Reassembling Skeleton over and over while fueling its return cost with the Treasure tokens generated by Pitiless Plunderer. The real secret to turning this into a productive cycle, however, lies in Delney, Streetwise Lookout; because Pitiless Plunderer's power is 2 or less, Delney causes its death trigger to double every single time the Skeleton hits the graveyard. This leaves us with an extra Treasure on every iteration, netting infinite mana along with infinite sacrifice, entry, and death triggers to overwhelm our opponents.