Requires

Double Major must be in hand. Kalamax, the Stormsire must be on the battlefield. Dualcaster Mage must be in hand. Kalamax is tapped. You have not cast another instant this turn. Mana needed:

Steps

1. Cast Dualcaster Mage by paying .
2. Holding priority, cast Double Major targeting Dualcaster Mage by paying .
3. Kalamax triggers, copying the Double Major, targeting Dualcaster Mage.
4. Resolve the copied Double Major, resolving a copy of Dualcaster Mage.
5. The Dualcaster Mage copy enters, copying Double Major, targeting Dualcaster Mage.
6. Repeat from step 4.

Results