を元に

… back to its original state

→ を
phrase Rare #34,426
… back to its original state In these examples, it is followed by 戻す, meaning “to put back” or “to restore.”
JA: 本を元に戻してください。
EN: Please put the book back where it was.

こいつを元に戻してくれ!

Put this back the way it was!

— きっと、うまくいく (2009)

陣形を元に戻せ!

Restore the formation!

— レッドクリフ Part I (2008)