Phyrexian Altar + Dualcaster Mage + Graceful Reprieve

Phyrexian Altar

Dualcaster Mage

Graceful Reprieve

How it works

1. Cast Graceful Reprieve by paying its mana cost.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, copying Graceful Reprieve, with the copy targeting Dualcaster Mage.
4. Resolve the copy of Graceful Reprieve.
5. Holding priority, activate Phyrexian Altar by sacrificing Dualcaster Mage.
6. When Dualcaster Mage dies, Graceful Reprieve triggers, returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.