In the mansion, the teams face even more strangeness. Hallways go in infinite circles before straightening out, skeletons with mischievous smiles on their faces hide behind doors that go nowhere, paintings come to life as robots emerge from the walls, and huge spiderwebs hang above bottomless pits that lead to oblivion. There is even a well in the mansion's center that opens up into a distorted, multicolored pocket dimension filled with pumpkin-headed ghosts.
The pocket dimension has a strange water—like background representing the inside of the well that changes color with the appropriate formation. Once the three formations are completed, the team (Sonic or Dark) arrive on the outside of the mansion in a giant reservoir with a Goal Ring in the center.
Mystic Mansion, much like Hang Castle, is filled with booby traps, such as the pumpkin-headed ghosts that appear, or the trolleys. There is also a special enemy that only appears in Mystic Mansion and Hang Castle called the E-1009 Egg Bishop. These red clad robots wear wizard caps and carry around a scepter. Instead of attacking, they can perform incantations or spells of some kind that heal their robot comrades when the player damages them. This robot also has a unique Jekyll and Hyde type design with two personalities, as they can flip over and transform into their alter ego, the E-1010 Egg Magician. This sinister blue robot can put a curse on the ground to create a vacuum that sucks rings from anyone unlucky enough to run into it. It will not flip faces of its own accord, but only if the player forces it do so by creating a tornado in Speed Formation.
After managing to get inside of the fortress Hang Castle takes place on the outside of, Team Sonic must escape the mansion located inside to intercept the Egg Fleet. Team Dark must escape to interrogate Eggman. Team Rose must escape to rescue Froggy and Chocola. Team Chaotix must blow out the 60 red torches in the mansion to escape. When the level is beaten by Team Dark or Team Sonic, players will find themselves standing in a giant, ghostless, calm reservoir on top of Hang Castle.
Rank Requirements (Normal Missions)
Escape the haunted castle!
Escape the crazy castle!
Escape the haunted house!
Blow out all the red torches!
Rank Requirements (Extra Missions)
Get to the goal ring within 7 minutes!
Defeat 100 enemies! (Time minutes.)
Collect 200 rings! (Time in minutes.)
Blow out all of the blue torches!
Lasers and rip lines will occasionally block the player's path in this level, but if Espio is invisible, he can slip through them.
This is the only level where all teams start at the exact same point.
In the very first room, there is a picture of the whale-shaped island from Seaside Hill.
Every time the player enters a room where the door has the usual skulls, another part of the level's music will be added until the player gets the full skull.
The skeletons in Mystic Mansion resemble Jack Skellington, the main character from the Tim Burton made Disney film The Nightmare Before Christmas. This was most likely intentional. They also resemble the skeletons from Corpse Bride, another film made by Tim Burton.
Team Rose is the only team to have another door located in the room with the giant skeleton statue which is how they escape the castle.
The three colors of the pocket dimension's areas represents the colors of the team formations; blue (Speed type), yellow (Fly type) and red (Power Type).