Time Sieve + Myr Battlesphere + Helm of the Host

Time Sieve

Myr Battlesphere

Helm of the Host

How it works

1. At the beginning of your combat phase, Helm of the Host triggers, creating a token copy of Myr Battlesphere with haste.
2. The Myr Battlesphere token enters the battlefield, creating four 1/1 Myr creature tokens.
3. Activate Time Sieve by tapping it, sacrificing the Myr Battlesphere token and sacrificing the four Myr tokens, causing you to take an extra turn after this one.
4. Repeat each turn.