Ashnod's Altar + Dualcaster Mage + Behold the Sinister Six!

Ashnod's Altar

Dualcaster Mage

Behold the Sinister Six!

How it works

1. Cast Behold the Sinister Six! by paying its mana cost
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, targeting Behold the Sinister Six!.
4. Holding priority, activate Ashnod's Altar by sacrificing Dualcaster Mage.
5. Resolve the Dualcaster Mage trigger, copying Behold the Sinister Six!, with the copy targeting Dualcaster Mage
6. Resolve the Behold the Sinister Six! copy, returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.

This loop turns a single massive spell into an unstoppable cycle of resurrection and sacrifice, anchored by Ashnod's Altar to fund the magic while converting each iteration into a pair of colorless mana. You cast Behold the Sinister Six! to seed your graveyard with options, then drop Dualcaster Mage into the mix so its enter-the-battlefield ability can copy the original sorcery. By sacrificing the Mage to Ashnod's Altar in response, you clear the way for the copied Behold the Sinister Six! to pull Dualcaster Mage right back out of the graveyard to do it all over again.