The Golden Staff, originally known as the Ocean-Pacifying Divine Needle, also called the Ruyi Staff or the Lingyang Staff, was used by Da Yu when he tamed the floods...
The Dragon King originally wanted to use this divine needle to show off, but the Monkey King possessed heaven-defying abilities and subdued it. In the Monkey King's hands, it could grow or shrink, lengthen or shorten, harden or soften. It could transform into the right size to perform the right tasks. It could ward off evil and drive away demons; it was an object of ultimate firmness and yang energy. Following the Monkey King to vanquish demons and ghosts, it was truly invincible, making those little demons scream in misery — just as miserable as Mimi and Reba were at this moment.
Su Yu often felt that he was that all-powerful Monkey King, because like the Great Sage, he possessed a Ruyi Golden Staff.
Chapter 220