Time Sieve + Myr Battlesphere + Planar Bridge + Wheel of Sun and Moon

Time Sieve

Myr Battlesphere

Planar Bridge

Wheel of Sun and Moon

How it works

1. Activate Planar Bridge by paying 8 and tapping it, causing you to search your library for Myr Battlesphere and put it onto the battlefield.
2. When Myr Battlesphere enters the battlefield, it triggers, creating four 1/1 Myr artifact creature tokens.
3. Activate Time Sieve by tapping it, sacrificing Myr Battlesphere and the four Myr tokens.
4. Myr Battlesphere is put on the bottom of your library instead of in your graveyard due to Wheel of Sun and Moon.
5. Resolve the Time Sieve ability, causing you to take an extra turn after this one.
6. Repeat each turn.

This clever loop uses Planar Bridge as your engine to continually tutor Myr Battlesphere straight onto the battlefield, instantly generating a squad of four Myr artifact tokens the moment it arrives. You then cash in that mechanical army along with the Battlesphere itself to fuel Time Sieve, sacrificing all five artifacts to secure an extra turn. Meanwhile, Wheel of Sun and Moon quietly alters the rules of the graveyard by tucking your sacrificed Myr Battlesphere right back to the bottom of your library, ensuring it is always primed for Planar Bridge to fetch it back out on the very next turn.