Dualcaster Mage + Phantom Train + Abnormal Endurance

Dualcaster Mage

Phantom Train

Abnormal Endurance

How it works

1. Cast Abnormal Endurance by paying its mana cost.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, copying Abnormal Endurance, with the copy targeting Dualcaster Mage.
4. Resolve the copy of Abnormal Endurance.
5. Holding priority, activate Phantom Train by sacrificing Dualcaster Mage.
6. When Dualcaster Mage dies, it triggers, returning it from your graveyard to the battlefield.
7. Repeat from step 3.
8. Resolve all Phantom Train abilities from step 5.

This loop turns a clever timing trick into an endless cycle by having Dualcaster Mage repeatedly copy Abnormal Endurance to save itself from the sacrifice required by Phantom Train. When you sacrifice the Mage to fuel Phantom Train's ability—which animates it and pumps it with +1/+1 counters—the delayed-trigger effect granted by the Endurance returns the Mage right back to the battlefield. Once returned, Dualcaster Mage triggers anew to copy another Abnormal Endurance, letting you repeat the whole process indefinitely for boundless enters-the-battlefield triggers, deaths, and massive creature growth.