Yarus, Roar of the Old Gods, Ashcloud Phoenix, and Phantom Train

Prerequisites

• Yarus, Roar of the Old Gods on the battlefield
• Ashcloud Phoenix on the battlefield
• Phantom Train on the battlefield

Steps

1. Activate Phantom Train by sacrificing Ashcloud Phoenix
2. When Ashcloud Phoenix dies, its first ability triggers, returning it from your graveyard to the battlefield face-down
3. Resolve the Phantom Train ability Activate Phantom Train by sacrificing Ashcloud Phoenix
4. Yarus' second ability triggers, returning Ashcloud Phoenix from your graveyard to the battlefield face down, and then turning it face up
5. Ashcloud Phoenix's second ability triggers, dealing 2 damage to each player
6. Resolve the Phantom Train ability Repeat

Results

• Near-infinite ETB
• Near-infinite LTB
• Near-infinite death triggers
• Near-infinite sacrifice triggers
• Near-infinite damage to all players
• Near-infinite +1/+1 counters on a creature