Dross Scorpion, Detective's Satchel, and Umbral Collar Zealot

Prerequisites

• Dross Scorpion on the battlefield
• Detective's Satchel on the battlefield
• Umbral Collar Zealot on the battlefield

Steps

1. Activate Detective's Satchel by tapping it, creating a 1/1 Thopter artifact creature token
2. Activate Umbral Collar Zealot by sacrificing the Thopter
3. When the Thopter dies, Dross Scorpion triggers, untapping Detective's Satchel
4. Resolve the Umbral Collar Zealot ability
5. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite surveil 1