Dualcaster Mage + Yahenni, Undying Partisan + Abnormal Endurance

Dualcaster Mage

Yahenni, Undying Partisan

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 Yahenni 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 Yahenni abilities from step 5.

This clever loop puts Dualcaster Mage's spell-copying ability on an infinite treadmill by targeting Abnormal Endurance, which ensures the Mage springs right back to the battlefield every time it hits the graveyard. While the Mage endlessly dies and re-enters, Yahenni, Undying Partisan acts as both the willing executioner through its sacrifice outlet and the ultimate beneficiary, growing infinitely large with +1/+1 counters as the creature sacrifices rack up.