Traveling Plague, Umbral Collar Zealot, and Siona, Captain of the Pyleas

Prerequisites

• Traveling Plague in hand
• Umbral Collar Zealot on the battlefield
• Siona, Captain of the Pyleas on the battlefield
• available

Steps

1. Cast Traveling Plague by paying , attaching it to another creature you control
2. When Traveling Plague enters, Siona triggers, creating a creature token
3. Activate Umbral Collar Zealot by sacrificing the creature Traveling Plague is attached to
4. When the creature dies, Traveling Plague triggers, returning itself from your graveyard to the battlefield attached to the token created in step 2
5. When Traveling Plague enters, Siona triggers, creating a creature token
6. Resolve the Umbral Collar Zealot ability
7. Repeat from step 3

Results

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