Romana II, and Intruder Alarm

Prerequisites

• Romana II on the battlefield
• Intruder Alarm on the battlefield

Steps

1. Activate any number of creatures by tapping them, adding at least
2. Activate Romana II by paying and tapping it, creating a copy of a creature token that entered the battlefield this turn
3. When the creature token enters, Intruder Alarm triggers, untapping all creatures
4. Repeat

Results

• Infinite ETB
• Infinite creature tokens
• Infinite mana creatures you control can produce
• Infinite untap of all creatures