Altar of Dementia + Dualcaster Mage + Leonardo's Technique

Altar of Dementia

Dualcaster Mage

Leonardo's Technique

How it works

1. Cast Leonardo's Technique by paying its mana cost, targeting any applicable target.
2. Holding priority, cast Dualcaster Mage by paying its mana cost.
3. When Dualcaster Mage enters, it triggers, targeting Leonardo's Technique.
4. Holding priority, activate Altar of Dementia by sacrificing Dualcaster Mage.
5. Resolve the Dualcaster Mage trigger, copying Leonardo's Technique, with the copy targeting Dualcaster Mage
6. Resolve the Leonardo's Technique copy, returning Dualcaster Mage from your graveyard to the battlefield.
7. Repeat from step 3.