Boonweaver Giant, Unholy Indenture, and Phantom Train

Prerequisites

• Boonweaver Giant on the battlefield
• Unholy Indenture on the battlefield
• Phantom Train on the battlefield

Steps

1. Activate Phantom Train by sacrificing Boonweaver Giant When Boonweaver Giant dies, Unholy Indenture triggers, returning Boonweaver Giant from your graveyard to the battlefield When Boonweaver Giant enters, it triggers, returning Unholy Indenture from your graveyard to the battlefield attached to Boonweaver Giant
2. Resolve the Phantom Train ability from step 1
3. Repeat

Results

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