Hidden Palace Zone

Hidden Palace Zone is a major location in Sonic.exe: The Spirits of Hell.

Appearance
Hidden Palace Zone is a giant cavern inside the volcano of Angel Island filled with neon cyan crystals that form the walls and ceiling. A giant luminous entrance in the distance shines light into the cave and the center of the Zone is a blue, castle-like structure housing the Master Emerald.

Dr. Robotnik's section is based on the scrapped Hidden Palace Zone Sonic the Hedgehog 2. The area is full of golden yellow rock for the walls and ceiling, grand cathedrals, green pipes and the regal, crumbling remains of ancient civilizations.

Role in Round 1
After each character's section in the save select screen, upon trying to select any of the files you will play through a regular platforming section as each of the characters who are still alive. The survivors will meet up at the Master Emerald shrine, where the Emerald will show them Sonic being possessed by Exeller before they plan their next move.

Tails Solo Route
Tails waits for a bit, but nobody else shows up. He is scared and concludes that Knuckles is dead before the Master Emerald shows him Sonic being possessed. Tails realises that he needs to warn everyone, but for that he needs the Tornado. Using the Master Emerald, he warps back to Green Hill Zone.

Knuckles Solo Route
Knuckles waits for a bit, but nobody else shows up.

Robotnik Solo Route
Robotnik waits for a bit, but nobody else shows up. He decides that his best move would be to hide out in Sky Base Zone as he would be protected by his Badniks and it is very high in the air. The Emerald shows him Sonic being possessed before he uses it to warp to Sky Base.

Tails and Knuckles Duo Route
Tails asks Knuckles what to do and suggests they call the Freedom Fighters for help, but Knuckles says that they are safe in Hidden Palace. However, Tails has a bad feeling that Sonic knows where they are and wonders if Robotnik corrupted him. However, Knuckles says that they destroyed the Death Egg so he shouldn't have enough power. The Master Emerald then shows the two Exeller possessing Sonic. Knuckles has a plan on how to purge Exeller from Sonic's body, but he must being standing still for it to work. Tails suggests they lure him to Mecha Green Hill Zone as the Zone contains lots of distractions. Knuckles agrees, and uses the Master Emerald to teleport them there.

Tails and Robotnik Duo Route
Tails asks Robotnik why he's here, and Robotnik explains that Sonic tried to hunt him down too. They hope that Knuckles is OK before the Master Emerald shows them Sonic being possessed by Exeller. Tails says that they need to remove Exeller from Sonic's body to save him, and Robotnik suggests that they go to Metropolis Zone as he has a lab there that should be heavily defended. Tails agrees, as the lava and traps could help slow Exeller down, before they use the Master Emerald to warp to Metropolis Zone.

Knuckles and Robotnik Duo Route
Knuckles angrily accuses Robotnik of corrupting Sonic and tells him to stay away, even when Robotnik insists that Sonic hunted him as well. Robotnik argues that if he did corrupt Sonic then he wouldn't be here, and Knuckles lets his guard down, though he warns Robotnik that he still doesn't trust him. The Master Emerald then shows the two Sonic being possessed by Exeller. Robotnik gets an idea, suggesting they go to Spring Yard Zone and work together to get a Chaos Emerald. Knuckles is wary, but agrees and uses the Master Emerald to take them to Spring Yard Zone.