Dualcaster Mage, and Siren's Ruse

Prerequisites

• Dualcaster Mage in hand
• Siren's Ruse in hand
• available

Steps

1. Cast Siren's Ruse by paying its mana cost
2. Holding priority, cast Dualcaster Mage by paying its mana cost
3. When Dualcaster Mage enters, it triggers, copying Siren's Ruse, with the copy targeting Dualcaster Mage
4. Resolve the copy of Siren's Ruse, blinking Dualcaster Mage
5. Repeat from step 3

Results

• Infinite ETB
• Infinite LTB
• Infinite magecraft triggers