Agatha's Soul Cauldron, Pheres-Band Tromper, and Ioreth of the Healing House

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Pheres-Band Tromper on the battlefield
• Ioreth of the Healing House in exile

Steps

1. Activate Pheres-Band Tromper using Ioreth of the Healing House's ability by tapping it, untapping another creature you control that has a +1/+1 counter on it
2. Activate the other creature using Ioreth of the Healing House's ability by tapping it, untapping Pheres-Band Tromper Pheres-Band Tromper triggers, putting a +1/+1 counter on it
3. Repeat

Results

• Infinite +1/+1 counters on a creature