This article is a stub.
Hidden Palace Zone in Sonic & Knuckles is a transitional level between Lava Reef Zone and Sky Sanctuary Zone. It consists of a single act, and is the shortest level in the game. It is also the only level in any of the Mega Drive-era Sonic the Hedgehog games that is devoted to plot progression. The stage first appeared in the Sonic 2 Beta.
One of the distinct features of this zone is the mural foretelling the events at Doomsday Zone of the fight between the Great Eggman Robo (Unless you don't have the emeralds).
The Hidden Palace Zone in user:Mystic Monkey fiction
At the heart of Angel Island is a large cave where crystals grow. This cave is also where the ruins of an Echidna palace stay (which resembles a blend of Aztec/Roman architecture) this palace was constructed by the Knuckles Tribe when Angel Island arose from the Earth.
The palace still has the mural as well as a secret library which holds records of history and lore of the ancient times.
While the Shrine of the Master Emerald is located on a small independant floating island (as seen in Sonic Adventure), this island can be relocated into a special area of the Hidden Palace Zone under such emergencies.