Time Sieve + Myr Battlesphere + Teleportation Circle + Oko, Thief of Crowns

Time Sieve

Myr Battlesphere

Teleportation Circle

Oko, Thief of Crowns

How it works

1. Activate Oko's first loyalty ability by putting two loyalty counters on it, creating a Food artifact token.
2. At the beginning of your end step, Teleportation Circle triggers, blinking Myr Battlesphere.
3. When Myr Battlesphere enters the battlefield, its first ability triggers, creating four 1/1 Myr artifact creature tokens.
4. Activate Time Sieve by tapping it and sacrificing the Myrs and Food, causing you to take an extra turn after this one.
5. Repeat each turn.