At a desert far from Megapolis, MK and the others were training while Pigsy was preparing food for them.
Meanwhile, the Lady Bone Demon and the Mayor put the remaining ingredients into the Trigram Furnace to create the bone mech, including the Spider Queen. Once the mech was created, Lady Bone Demon uses to mech to attack MK. Although MK was able to destroy the mech, he lost some of his powers and Tang realized that MK was hiding something. Having no other choice, MK came clean to his friends by saying that he was keeping Lady Bone Demon a secret from them so he can protect them. However, Lady Bone Demon arrived and defeated MK's friends. She then rebuilds the bone mech into the Bone Scorpion.
As MK continued to use his powers, Tang acknowledged that the Lady Bone Demon grew stronger every time MK used his powers. Moments later, the bone mech grabs MK and tried to crush him. In order to free himself, MK creates the Monkey King Warrior Mech and destroyed the Bone Scorpion, but at the cost of him losing more of his powers and Lady Bone Demon regaining her true form.
After Lady Bone Demon changed into her true form, she rebuild the bone mech into the Bone Demon and destroyed the Monkey King Warrior Mech. She then steals the remaining of MK's powers, preventing him from lifting the Golden Staff. Before she could finish him off, Monkey King arrives and takes MK far away from her. Although she failed to defeat MK, Lady Bone Demon became closer into achieving her goal.
After MK and the Monkey King met up with the others, MK told Monkey King that they could've done something. Monkey King, however, stated that they can't do anything to stop Lady Bone Demon now. Angered, Pigsy gets mad at Monkey King for not being there for MK until Sandy yells at everyone to stop, thinking that Monkey King should tell them why he left. Monkey King explained that the real reason he left wasn't because he wanted to go on vacation, but to actually find a weapon that could defeat the Lady Bone Demon. After hearing this, MK tells Monkey King that he and his team are going with him. Although he refused at first, Monkey King accepted MK's suggestion and the six go on a journey to the west.
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