Dualcaster Mage, Grub's Command, and Rukarumel, Biologist

Prerequisites

• Dualcaster Mage in hand
• Grub's Command in hand
• Rukarumel, Biologist on the battlefield
• available

Steps

1. Cast Grub's Command 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 Grub's Command, targeting Dualcaster Mage
4. Resolve the copy of Grub's Command, creating a token copy of Dualcaster Mage
5. Repeat from step 3

Results

• Destroy any number of creatures
• Infinite creature ETB
• Infinite creature tokens
• Infinite magecraft triggers
• Infinite mill
• Infinite self-mill
• Infinitely large creatures you control until end of turn
• Put all Goblin cards from your library into your hand