Mazzy, Truesword Paladin, Ashnod's Altar, Gift of Immortality, and Contract Hero

Prerequisites

• Mazzy, Truesword Paladin on the battlefield
• Ashnod's Altar on the battlefield
• Gift of Immortality on the battlefield
• Contract Hero on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Contract Hero, adding
2. When Contract Hero dies, Mazzy's second ability and Gift of Immortality trigger
3. Resolve the Mazzy trigger, exiling Gift of Immortality with the ability to cast it until end of your next turn
4. Resolve the Gift of Immortality trigger, returning Contract Hero from your graveyard to the battlefield
5. When Contract Hero enters, it triggers, creating a Treasure token
6. Activate the Treasure by tapping and sacrificing it, adding
7. Cast Gift of Immortality from exile by paying , attaching it to Contract Hero
8. Repeat

Results

• Infinite sacrifice triggers
• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite storm count