Hell's Caretaker, Breaching Hippocamp, and Deceiver Exarch

Prerequisites

• Hell's Caretaker on the battlefield
• Breaching Hippocamp on the battlefield
• Deceiver Exarch in the graveyard

Steps

1. During your upkeep, activate Hell's Caretaker by sacrificing Corridor Montior, returning Deceiver Exarch from your graveyard to the battlefield
2. Deceiver Exarch enters the battlefield, untapping Hell's Caretaker
3. Activate Hell's Caretaker by sacrificing Deceiver Exarch, returning Breaching Hippocamp from your graveyard to the battlefield
4. Breaching Hippocamp enters the battlefield, untapping Hell's Caretaker
5. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers