Exhume + Dualcaster Mage + Yahenni, Undying Partisan

Exhume

Dualcaster Mage

Yahenni, Undying Partisan

How it works

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

This clever loop begins when you cast Exhume to pull a creature from your graveyard, immediately interrupting it by flashing in Dualcaster Mage to copy the spell on the stack. Before that copy resolves, you feed Dualcaster Mage to Yahenni, Undying Partisan, which not only buffs Yahenni with a +1/+1 counter but sends the Mage right back to the graveyard just in time for the resolving Exhume copy to resurrect it. This creates a perpetual cycle of entering and dying, generating an infinite storm of sacrifices and creature triggers while simultaneously forcing each opponent to reanimate every creature from their own graveyard.