Dualcaster Mage + Sevinne's Reclamation + Yahenni, Undying Partisan

Dualcaster Mage

Sevinne's Reclamation

Yahenni, Undying Partisan

How it works

1. Cast Sevinne's Reclamation by paying its mana cost, targeting any applicable target.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, targeting Sevinne's Reclamation.
4. Holding priority, activate Yahenni by sacrificing Dualcaster Mage.
5. Resolve the Dualcaster Mage trigger, copying Sevinne's Reclamation, with the copy targeting Dualcaster Mage
6. Resolve the Sevinne's Reclamation copy, returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.

This loop turns a simple recursion spell into an endless engine by using Dualcaster Mage to continuously copy Sevinne's Reclamation from the graveyard. While the Mage creates the copies it needs to keep itself coming back, Yahenni, Undying Partisan acts as the crucial sacrifice outlet that lets you feed the loop at instant speed. Every iteration recycles the Mage back to the battlefield while triggering endless death counts and sacrifices, making this a potent loop in any format where these cards are legal.