Urza, Lord High Artificer, Scaretiller, Vesuva, Gods' Eye, Gate to the Reikai, and Intruder Alarm

Prerequisites

• Urza, Lord High Artificer on the battlefield
• Scaretiller on the battlefield
• Vesuva in the graveyard
• Gods' Eye, Gate to the Reikai on the battlefield
• Intruder Alarm on the battlefield

Steps

1. Activate Urza by tapping Scaretiller, adding
2. Scaretiller triggers, returning Vesuva from your graveyard to the battlefield as a copy of Gods' Eye
3. Put Vesuva into your graveyard due to the legend rule
4. Vesuva triggers, creating a 1/1 Spirit creature token
5. When the Spirit enters the battlefield, Intruder Alarm triggers, untapping all creatures
6. Repeat

Results

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