Requires

Reset must be in hand. Dualcaster Mage must be in hand. Riptide Laboratory must be on the battlefield. Other lands that can produce on the battlefield. Mana needed:

Steps

1. During an opponent turn, after their upkeep, cast Reset for .
2. In response, cast Dualcaster Mage at instant speed for .
3. Resolve Dualcaster Mage, and target Reset with his triggered ETB ability to copy Reset.
4. Resolve the Reset copy untapping your lands including Riptide Laboratory.
5. In response to the original Reset still on the stack, activate Riptide Laboratory's activated ability for and tap targeting Dualcaster Mage.
6. Resolve Riptide Laboratory's activated ability returning Dualcaster Mage to your hand.
7. Tap all lands other than Riptide Laboratory.
8. Repeat.

Results