Infinite LTB, Infinite Mutagen tokens, Infinite colorless mana, Infinite death triggers, Infinite sacrifice triggers, Infinite storm count, Infinite +1/+1 counters on creatures you control, Infinite ETB
Cast Metalwork Colossus by paying , which enters with at least two +1/+1 counters on it due to Bioengineered Future.
Activate Ashnod's Altar by sacrificing Metalwork Colossus.
When Metalwork Colossus dies, The Ooze triggers, creating a Mutagen token for each +1/+1 counter Metalwork Colossus had.
Activate Metalwork Colossus by sacrificing two Mutagens, returning it from your graveyard to your hand.
Repeat.
Component Cards
How It Works
Cast Metalwork Colossus by paying , which enters with at least two +1/+1 counters on it due to Bioengineered Future.
Activate Ashnod's Altar by sacrificing Metalwork Colossus.
When Metalwork Colossus dies, The Ooze triggers, creating a Mutagen token for each +1/+1 counter Metalwork Colossus had.
Activate Metalwork Colossus by sacrificing two Mutagens, returning it from your graveyard to your hand.
Repeat.