Cavalier of Night, Paleontologist's Pick-Axe // Dinosaur Headdress, Priest of Gix, and Yahenni, Undying Partisan

Prerequisites

• Cavalier of Night in exile
• Paleontologist's Pick-Axe // Dinosaur Headdress on the battlefield
• Priest of Gix on the battlefield
• Yahenni, Undying Partisan on the battlefield
• Paleontologist's Pick-Axe on the battlefield as Dinosaur Headdress
• Cavalier of Night exiled by Dinosaur Headdress
• available

Steps

1. Activate Dinosaur Headdress' equip ability by paying , attaching it to Priest of Gix and causing Priest of Gix to become a copy of Cavalier of Night
2. Activate Yahenni by sacrificing Priest of Gix
3. When Priest of Gix dies, its second ability triggers, returning itself from your graveyard to the battlefield
4. When Priest of Gix enters the battlefield, it triggers, adding
5. Resolve the Yahenni ability, causing it to gain indestructible until end of turn
6. Repeat

Results

• Infinite black mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers