Ratchet, Field Medic // Ratchet, Rescue Racer, Mysterious Limousine, Sludge Strider, and Krark-Clan Ironworks

Prerequisites

• Ratchet, Field Medic // Ratchet, Rescue Racer on the battlefield
• Mysterious Limousine on the battlefield
• Sludge Strider on the battlefield
• Krark-Clan Ironworks on the battlefield
• Ratchet on the battlefield as Ratchet, Field Medic
• You have gained at least four life this turn

Steps

1. Activate Krark-Clan Ironworks by sacrificing Mysterious Limousine, adding
2. Sludge Strider triggers, causing you to pay to gain 1 life and cause an opponent to lose 1 life
3. Ratchet, Field Medic triggers, converting it into Ratchet, Rescue Racer, and returning Mysterious Limousine from your graveyard to the battlefield
4. When Mysterious Limousine enters the battlefield, it and Sludge Strider trigger
5. Resolve the Mysterious Limousine trigger, exiling Ratchet until Mysterious Limousine leaves the battlefield
6. Resolve the Sludge Strider trigger, choosing not to pay
7. Activate Krark-Clan Ironworks by sacrificing Mysterious Limousine, adding
8. When Mysterious Limousine leaves the battlefield, Ratchet returns to the battlefield from exile as Ratchet, Field Medic
9. Repeat from step 2

Results

• Infinite colorless mana
• Infinite ETB
• Infinite lifegain
• Infinite lifegain triggers
• Infinite lifeloss
• Infinite LTB