Metalwork Colossus, The Ooze, Ashnod's Altar, and Master Biomancer

Prerequisites

• Metalwork Colossus in hand
• The Ooze on the battlefield
• Ashnod's Altar on the battlefield
• Master Biomancer on the battlefield

Steps

1. Cast Metalwork Colossus by paying , which enters with at least two +1/+1 counters on it due to Master Biomancer
2. Activate Ashnod's Altar 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. Activate Metalwork Colossus by sacrificing two Mutagens, returning it from your graveyard to your hand
5. Repeat

Results

• Infinite +1/+1 counters on creatures you control
• Infinite ETB
• Infinite LTB
• Infinite Mutagen tokens
• Infinite colorless mana
• Infinite death triggers
• Infinite sacrifice triggers
• Infinite storm count