Metalwork Colossus, The Ooze, Phantom Train, and Bioengineered Future

Prerequisites

• Metalwork Colossus in hand
• The Ooze on the battlefield
• Phantom Train on the battlefield
• Bioengineered Future on the battlefield

Steps

1. Cast Metalwork Colossus by paying , which enters with at least two +1/+1 counters on it due to Bioengineered Future
2. Activate Phantom Train by sacrificing Metalwork Colossus
3. When Metalwork Colossus dies, The Ooze triggers, creating a Mutagen token for each +1/+1 counter Metalwork Colossus had
4. Resolve the Phantom Train ability
5. Activate Metalwork Colossus by sacrificing two Mutagens, returning it from your graveyard to your hand
6. Repeat

Results

• Infinite artifact ETB
• Infinite artifact LTB
• Infinite artifact sacrifice triggers
• Infinite artifact tokens
• Infinite +1/+1 counters on a creature
• Infinite creature ETB
• Infinite creature LTB
• Infinite Mutagen tokens
• Infinite death triggers
• Infinite creature sacrifice triggers
• Infinite storm count