Jan Jansen, Chaos Crafter, Pitiless Plunderer, Ashnod's Altar, and Crab Umbra

Prerequisites

• Jan Jansen, Chaos Crafter on the battlefield
• Pitiless Plunderer on the battlefield
• Ashnod's Altar on the battlefield
• Crab Umbra on the battlefield
• You control at least one additional noncreature artifact

Steps

1. Activate Jan Jansen's second ability by tapping it and sacrificing any other noncreature artifact, creating two 1/1 Construct creature tokens
2. Activate Ashnod's Altar twice by sacrificing both Construct tokens, adding
3. When the Constructs die, Pitiless Plunderer triggers twice, creating two Treasure tokens
4. Activate a Treasure by tapping and sacrificing it, adding
5. Activate Crab Umbra by paying , untapping Jan Jansen
6. Repeat

Results

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