Carnage, Crimson Chaos, Saffi Eriksdotter, and Phantom Train

Prerequisites

• Carnage, Crimson Chaos in hand
• Saffi Eriksdotter in the graveyard
• Phantom Train on the battlefield

Steps

1. Cast Carnage by paying
2. When Carnage enters, it triggers, returning Saffi from your graveyard to the battlefield
3. Activate Saffi by sacrificing it, targeting Carnage
4. Activate Phantom Train by sacrificing Carnage
5. When Carnage dies, Saffi triggers, returning Carnage from your graveyard to the battlefield
6. When Carnage enters, it triggers, returning Saffi from your graveyard to the battlefield
7. Resolve the Phantom Train ability
8. Repeat from step 3

Results

• Infinite +1/+1 counters on a creature
• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers