Magnanimous Magistrate, Doubling Season, Pollenbright Druid, and Ashnod's Altar

Prerequisites

• Magnanimous Magistrate on the battlefield
• Doubling Season on the battlefield
• Pollenbright Druid on the battlefield
• Ashnod's Altar on the battlefield

Steps

1. Activate Ashnod's Altar by sacrificing Pollenbright Druid, adding
2. Pollenbright Druid dies, triggering Magnanimous Magistrate, causing you to remove two reprieve counters from Magnanimous Magistrate and return Pollenbright Druid from your graveyard to the battlefield
3. Pollenbright Druid enters the battlefield, causing you to proliferate, putting two reprieve counters on Magnanimous Magistrate
4. Repeat

Results

• Infinite colorless mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite proliferate
• Infinite sacrifice triggers