Romana II, There and Back Again, and Intruder Alarm

Prerequisites

• Romana II on the battlefield
• There and Back Again on the battlefield
• Intruder Alarm on the battlefield
• Romana II does not have summoning sickness
• There and Back Again has exactly two lore counters on it
• available

Steps

1. At the beginning of your precombat main phase, There and Back Again triggers, putting a lore counter on it
2. There and Back Again's third chapter ability triggers, creating a legendary 6/6 Smaug creature token and causing you to sacrifice There and Back Again
3. When Smaug enters the battlefield, Intruder Alarm triggers, untapping all creatures
4. Activate Romana II by paying and tapping it, creating a token copy of Smaug with haste
5. Put either Smaug token into your graveyard due to the legend rule
6. Intruder Alarm and the Smaug token that died trigger
7. Resolve the Intruder Alarm trigger, untapping all creatures
8. Resolve the Smaug trigger, creating fourteen Treasure tokens
9. Activate a Treasure by tapping and sacrificing it, adding
10. Repeat from step 4

Results

• Infinite LTB
• Infinite ETB
• Infinite colored mana
• Infinite death triggers
• Infinite untap of all creatures
• Infinite mana creatures you control can produce
• Infinite Treasure tokens