Mikaeus, the Unhallowed, Phantom Train, and Bristlebane Battler

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Phantom Train on the battlefield
• Bristlebane Battler on the battlefield

Steps

1. Activate Phantom Train by sacrificing Bristlebane Battler
2. When Bristlebane Battler dies, its undying ability triggers, returning it from your graveyard to the battlefield without a +1/+1 counter on it due to its replacement effect
3. Resolve the Phantom Train ability Repeat

Results

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