Dualcaster Mage, and Devastating Onslaught

Prerequisites

• Dualcaster Mage in hand
• Devastating Onslaught in hand
• available

Steps

1. Cast Devastating Onslaught by paying , targeting an artifact or creature you control
2. Holding priority, cast Dualcaster Mage by paying
3. When Dualcaster Mage enters the battlefield, it triggers, copying Devastating Onslaught, targeting Dualcaster Mage
4. Resolve the copy of Devastating Onslaught, creating a token copy of Dualcaster Mage
5. Repeat from step 3

Results

• Infinite ETB
• Infinite creature tokens with haste
• Infinite magecraft triggers