Requires

Encroaching Mycosynth must be on the battlefield. Dualcaster Mage must be in hand. Scrap Mastery must be in hand. Altar of Dementia must be on the battlefield. Mana needed:

Steps

1. Cast Scrap Mastery by paying .
2. In response, cast Dualcaster Mage by paying .
3. Dualcaster Mage enters the battlefield, copying Scrap Mastery.
4. Activate Altar of Dementia by sacrificing Dualcaster Mage, causing any player to mill two cards.
5. Resolve a copy of Scrap Mastery, swapping all nonland permanents you control with all nonland permanents in your graveyard.
6. Repeat from step 3.

Results