Time Sieve + Mycosynth Lattice + Rionya, Fire Dancer + Avenger of Zendikar

Time Sieve

Mycosynth Lattice

Rionya, Fire Dancer

Avenger of Zendikar

How it works

1. At the beginning of your combat phase, Rionya triggers, creating at least one token copy of Avenger of Zendikar with haste.
2. When the Avenger of Zendikar 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 Avenger of Zendikar token and the Plant tokens, causing you to take an extra turn after this one.
4. Repeat each turn.