Hawkeye's Bow, Ioreth of the Healing House, and Kelpie Guide

Prerequisites

• Hawkeye's Bow on the battlefield
• Ioreth of the Healing House on the battlefield
• Kelpie Guide on the battlefield

Steps

1. Activate Ioreth of the Healing House by tapping it, targeting Kelpie Guide
2. If Ioreth of the Healing House has Hawkeye's Bow attached to it, Hawkeye's Bow triggers, dealing 1 damage to each opponent
3. Resolve the Ioreth of the Healing House ability, untapping Kelpie Guide
4. Activate Kelpie Guide by tapping it, targeting Ioreth of the Healing House
5. If Kelpie Guide has Hawkeye's Bow attached to it, Hawkeye's Bow triggers, dealing 1 damage to each opponent
6. Resolve the Kelpie Guide ability, untapping Ioreth of the Healing House
7. Repeat

Results

• Infinite damage