Umbral Collar Zealot + Dualcaster Mage + Second Sunrise

Umbral Collar Zealot

Dualcaster Mage

Second Sunrise

How it works

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

This clever loop begins by casting Second Sunrise to set up a sweeping board-state recursion, but the real engine kicks into gear when you drop Dualcaster Mage to copy it on the stack. Before that copy resolves, you can feed your newly arrived wizard to Umbral Collar Zealot's sacrifice ability to surveil through your library and send Dualcaster Mage safely to the graveyard. When the copied Second Sunrise finally resolves, it pulls Dualcaster Mage right back onto the battlefield to copy the original spell all over again, generating an endless cascade of triggers and card filtering.