Urza, Prince of Kroog, Boommobile, and Kaya, Geist Hunter

Prerequisites

• Urza, Prince of Kroog on the battlefield
• Boommobile on the battlefield
• Kaya, Geist Hunter on the battlefield
• Kaya has at least two loyalty counters on it
• available

Steps

1. Activate Kaya's second loyalty ability by removing two loyalty counters from it, causing you to double any tokens you create this turn
2. Activate Urza by paying , creating two token copies of Boommobile that are 1/1 Soldier artifact creatures
3. When the Boommobile tokens enters the battlefield, they trigger, adding that can only be spent to activate abilities
4. Repeat from step 2

Results

• Infinite ETB
• Infinite damage
• Infinite creature tokens
• Infinite colored mana that can only be spent to activate abilities
• Infinite creature copies of artifacts you control