Phyrexian Altar + Dualcaster Mage + Feign Death

Phyrexian Altar

Dualcaster Mage

Feign Death

How it works

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