Requires

Dualcaster Mage must be on the battlefield. Echo Storm must be in hand. Encroaching Mycosynth must be on the battlefield. You've cast your commander from the command zone at least once this game. Mana needed:

Steps

1. Cast Echo Storm by paying , targeting Dualcaster Mage.
2. Echo Storm triggers, creating a copy of itself, targeting Dualcaster Mage.
3. Resolve the copy of Echo Storm, creating a token copy of Dualcaster Mage.
4. When the Dualcaster Mage token enters the battlefield, it triggers, creating a copy of Echo Storm, targeting Dualcaster Mage.
5. Repeat from step 3.

Results