Time Sieve, Encroaching Mycosynth, Helm of the Host, and Izoni, Thousand-Eyed

Prerequisites

• Time Sieve on the battlefield
• Encroaching Mycosynth on the battlefield
• Helm of the Host on the battlefield
• Izoni, Thousand-Eyed on the battlefield
• Helm of the Host attached to Izoni
• You have at least four creature cards in your graveyard

Steps

1. At the beginning of your combat phase, Helm of the Host triggers, creating a nonlegendary token copy of Izoni with haste
2. When the Izoni token enters the battlefield, it triggers, creating a number of 1/1 Insect creature tokens equal to the number of creature cards in your graveyard
3. Activate Time Sieve by tapping it and sacrificing five creature tokens, causing you to take an extra turn after this one
4. Repeat each turn

Results

• Infinite turns