Dualcaster Mage + Extract from Darkness + Phantom Train

Dualcaster Mage

Extract from Darkness

Phantom Train

How it works

1. Cast Extract from Darkness by paying its mana cost
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, targeting Extract from Darkness.
4. Holding priority, activate Phantom Train by sacrificing Dualcaster Mage.
5. Resolve the Dualcaster Mage trigger, copying Extract from Darkness
6. Resolve the Extract from Darkness copy, causing each player to mill two cards and returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.

This clever loop uses Phantom Train as a convenient sacrifice outlet to clear the way for Dualcaster Mage, which enters the battlefield and seizes the original Extract from Darkness by copying it on the stack. The resolved copy of Extract from Darkness then mills your library and reaches right into the graveyard to pull Dualcaster Mage straight back onto the battlefield, restarting the whole cycle. Because Phantom Train can constantly devour Dualcaster Mage for a +1/+1 counter while Extract from Darkness keeps resurrecting it, you effortlessly generate an endless storm of triggers and mill your opponents out in the process.