Time Sieve, Mycosynth Lattice, Helm of the Host, and Phylath, World Sculptor

Prerequisites

• Time Sieve on the battlefield
• Mycosynth Lattice on the battlefield
• Helm of the Host on the battlefield
• Phylath, World Sculptor on the battlefield
• You control at least four basic lands
• Helm of the Host attached to Phylath

Steps

1. At the beginning of your combat phase, Helm of the Host triggers, creating a nonlegendary token copy of Phylath with haste
2. When the Phylath token enters the battlefield, its first ability triggers, creating at least four 0/1 Plant creature tokens
3. Activate Time Sieve by tapping it, sacrificing the Phylath token and the Plant tokens, causing you to take an extra turn after this one
4. Repeat each turn

Results

• Infinite turns