Boonweaver Giant, Phantom Train, and Kaya's Ghostform

Prerequisites

• Boonweaver Giant on the battlefield
• Phantom Train on the battlefield
• Kaya's Ghostform on the battlefield

Steps

1. Activate Phantom Train by sacrificing Boonweaver Giant When Boonweaver Giant dies, Kaya's Ghostform triggers, returning Boonweaver Giant from your graveyard to the battlefield When Boonweaver Giant enters, it triggers, returning Kaya's Ghostform 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 ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers