Jackdaw Savior, Loyal Retainers, and Phantom Train

Prerequisites

• Jackdaw Savior on the battlefield
• Loyal Retainers in the graveyard
• Phantom Train on the battlefield

Steps

1. During your precombat main phase, activate Phantom Train by sacrificing the legendary creature with flying
2. When the creature dies, Jackdaw Savior triggers, returning Loyal Retainers from your graveyard to the battlefield
3. Resolve the Phantom Train ability, putting a +1/+1 counter on it
4. Activate Loyal Retainers by sacrificing it, returning the legendary creature with flying from your graveyard to the battlefield
5. Repeat

Results

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