Umbral Collar Zealot + Infuse with Vitality + Dualcaster Mage

Umbral Collar Zealot

Infuse with Vitality

Dualcaster Mage

How it works

1. Cast Infuse with Vitality by paying its mana cost.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, copying Infuse with Vitality, with the copy targeting Dualcaster Mage.
4. Resolve the copy of Infuse with Vitality.
5. Holding priority, activate Umbral Collar Zealot 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 Umbral Collar Zealot abilities from step 5.

This clever loop turns Dualcaster Mage into an immortal engine by targeting it with the very copy of Infuse with Vitality that the Mage itself generates upon entering the battlefield. Because Infuse with Vitality grants a delayed trigger that returns the creature to the battlefield when it dies, sacrificing Dualcaster Mage to Umbral Collar Zealot triggers both its return and the Zealot's surveil ability. Once the Mage returns, its entry ability triggers anew to copy Infuse with Vitality yet again, sustaining an endless cycle of sacrifices, lifegain, and library manipulation.