Time Sieve + Myr Battlesphere + Mortuary

Time Sieve

Myr Battlesphere

Mortuary

How it works

1. Cast Myr Battlesphere by paying 7.
2. Myr Battlesphere enters the battlefield, creating four 1/1 Myr creature tokens.
3. Activate Time Sieve by tapping it, sacrificing Myr Battlesphere and sacrificing the four Myr tokens.
4. When Myr Battlesphere dies, Mortuary triggers, putting Myr Battlesphere on top of your library from your graveyard.
5. Resolve the Time Sieve ability, causing you to take an extra turn after this one.
6. Move to your next turn, drawing Myr Battlesphere during your draw step.
7. Repeat.