Colfenor, the Last Yew, Gutter Grime, and Phantom Train

Prerequisites

• Colfenor, the Last Yew on the battlefield
• Gutter Grime on the battlefield
• Phantom Train on the battlefield

Steps

1. Cast the creature card in your hand by paying
2. Either that creature dies as a state-based action due to having zero toughness, or activate Phantom Train by sacrificing that creature
3. Gutter Grime triggers, putting a slime counter on it and creating a X/X Ooze creature token
4. Activate Phantom Train by sacrificing the Ooze
5. When the Ooze dies, Colfenor triggers, returning the creature card from your graveyard to your hand
6. Resolve the Phantom Train abilities, putting a +1/+1 counter on it each time
7. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite storm count
• Infinite +1/+1 counters on a creature
• Infinite creature tokens that are infinitely large