Monstropolis
First Appearance: KINGDOM HEARTS III (2019)
Origin: Monsters Inc (2001)
As they arrived at the doors of a colossal power company called Monsters, Incorporated, Sora, Donald, and Goofy discovered that Donald’s magic had transformed them into monsters, too. 
Inside, they were alarmed to find a pair of monsters with a little human girl, Boo, but one look at how happy Boo was convinced Sora that the monsters, Mike and Sulley, must be friendly. When the decidedly less friendly Unversed appeared in the company lobby, Sora volunteered to play exterminator.
Given the circumstances, they all agreed that getting Boo home safely should be their top priority. Her house 
was connected to Sulley and Mike’s company by a special door.
But their efforts to find it were cut short by sabotage: Randall, a former employee banished for his scheming, had returned and was eager to stage a comeback using the energy from negative emotions. Mikey, Sulley, and the rest battled their way out of the factory with a little help from Boo’s laugh energy.
Along their way back to the door vault, the gang were faced with power outages, explosions, fires, and other frustrations, but Sulley’s quick thinking (and a little heavy lifting) helped them find a shortcut.
Once again, they found themselves face-to-face with Randall. Jealous of Sulley and Mike’s success, he tried to use a huge Unversed to get them all out of the picture. Of course, it didn’t work. Sulley and Mike banished their rival from the factory again, and this time Sora used his Keyblade to lock the door behind Randall for good measure.
Just as Sulley and Mike were about to send Boo home, the Organization’s Vanitas appeared. He was the one who brought Randall back and furnished him with Unversed in order to gather negative emotions.
Vanitas revealed that Ventus, one of the missing Keyblade wielders, now sleeps inside of Sora, then attempted to rejoin with Ventus by force. Again, Sulley’s quick thinking saved the day. With an imposing roar, he overpowered Vanitas and saved Sora from who knows what fate.
With the roller-coaster quest for Boo’s door finally over, Sora, Donald, and Goofy said their good-byes to their little friend as she returned to her room. Next, it was time to bid Sulley and Mike farewell. They shared a few more laughs together, then said their thank-yous and got back to their usual business.
