Mortuary, Narcomoeba, Pitiless Plunderer, and Undercity Informer

Prerequisites

• Mortuary on the battlefield
• Narcomoeba on the battlefield
• Pitiless Plunderer on the battlefield
• Undercity Informer on the battlefield
• available

Steps

1. Activate Undercity Informer by paying and sacrificing Narcomoeba
2. When Narcomoeba dies, Mortuary and Pitiless Plunderer trigger
3. Resolve the Mortuary trigger, putting Narcomoeba on top of your library from your graveyard
4. Resolve the Pitiless Plunderer trigger, creating a Treasure token
5. Resolve the Undercity Informer ability, causing you to put Narcomoeba into your graveyard from the top of your library
6. Narcomoeba triggers, returning itself to the battlefield from your graveyard
7. Activate the Treasure by tapping and sacrificing it, adding
8. Repeat

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers
• Infinite self-mill