Dualcaster Mage, and Croaking Counterpart

Prerequisites

• Dualcaster Mage in hand
• Croaking Counterpart in hand
• You control at least one creature
• You have enough mana to cast Croaking Counterpart available

Steps

1. Cast Croaking Counterpart by paying its mana cost, targeting a creature you control
2. Holding priority, cast Dualcaster Mage by paying
3. When Dualcaster Mage enters the battlefield, it triggers, copying Croaking Counterpart, targeting Dualcaster Mage
4. Resolve the copy of Croaking Counterpart, creating a token copy of Dualcaster Mage that is a 1/1 Frog
5. Repeat from step 3

Results

• Infinite ETB
• Infinite creature tokens
• Infinite magecraft triggers