Ashnod's Altar, Faceless Butcher, and Karmic Guide

Prerequisites

• Ashnod's Altar on the battlefield
• Faceless Butcher in hand
• Karmic Guide on the battlefield
• available

Steps

1. Cast Faceless Butcher by paying its mana cost
2. When Faceless Butcher enters, its first ability triggers, exiling Karmic Guide
3. Activate Ashnod's Altar by sacrificing Faceless Butcher
4. When Faceless Butcher dies, its second ability triggers, returning Karmic Guide from exile to the battlefield
5. When Karmic Guide enters, it triggers, returning Faceless Butcher from your graveyard to the battlefield
6. When Faceless Butcher enters, its first ability triggers, exiling Karmic Guide
7. Repeat from step 3

Results

• Infinite ETB
• Infinite LTB
• Infinite colorless mana
• Infinite death triggers
• Infinite sacrifice triggers