Scrap Brain Zone: A giant factory built for building robots. Complete with buzzsaws and water slides.
Metropolis Zone: A giant factory built for building the Death Egg and Sky Fortress. Plenty of green (metal that is) and lava.
Sky Fortress Zone: A giant Airplane ten times bigger than Air Force one. It can fire large lasers, and has plenty of guards and propellers that dont serve any value what so ever.
Death Egg: Parody or Tribute? You decide. It was the death Star from star wars rebuilt with Eggman's face on it. Had no weapons at the time.
Wacky Workshop: A large workshop (hence the name) that the floor ould always bounce you up. Plenty of rotating platforms.
Metallic Madness: Eggman's main base. It really is no different than scrap brain zone, just minus the water slides.
Launch Base Zone: A large base built to rebuild the Death Egg on Angel Island. It had security lasers and alarms, and even knuckles as the head security guard.
Flying Battery Zone: A large blimp that could drop bombs and was used as a fast way to travel around the island. It was similar to Flying Fortress.
Death Egg Zone: This time you actually had to travel to its launch bay. It had overloaded security measures and distable gravity.
Mystic Ruins Base: A large base in the Mystic Ruins Jungle. It was mainly a airfield for the Egg Carrier.
Egg Carrier: A giant space ship looking aircraft with thousands of robotic airplanes denfending it. It had a sleeker mode in which it was small and compact to fly faster, and a larger mode with wings to fly slower and to by time before Sonic got to the bridge. It had a giant Cannon hidden in its nose capable of destroying airplanesand such, as the tornado's wing is the only thing ever hit by it.
Fire Bird: Rather or not this is an eggman base is unsure, but if not is was probably created from the dreams about eggman's bases. I giant flying fortress shaped like a phoenix that runs on Precious Stones. As its Precious Stones deplete, it loses power and its wings start to blow up. Once all Precious stones are taken, it transforms into a true phoenix, which is what the original dream was.
Riot Train: Rather or not this is an eggman base is unsure, but its similar to that of Eggman's train in the game made years later, Sonic next Gen. A large out of control train that is moving continuously on the tracks of dreams. It runs off of precious stones.
Hidden Base: A base hidden inside a pyrimid. But only a staging ground for his plans.
ARK: Technically not Eggman's base, it was built by his Grandfather. For more detail look in the Gerald section.
Bullit Station: A large base built in a canyon. It had several aireal railroads and plenty of giant cannons. A large amount of Shadow Androids were stored here.
Egg Fleet: an asortment of thousands upon thousands of giant airships. All airships were riminiscent of fish. For example, the battleships looked like swordfish, and some other bigger ships looked like whales. They all had extreme firepower.
Final Fortress: The flagship of the Egg Fleet, it looked like a giant stingray. Acording to knuckles, its 2o times bigger than the Egg Carrier. Filled with almost nothing but giant cannons and weak versions of the Egg Emperor.
Cyrptic Castle: A large castle owned by Eggman that GUN and the black Arms are always attacking. It seems to be haunted by ghosts and has a security system that if all giant lanterns are lit, then its protected in some way.
Circus Park: A giant park owned by Eggman thats always being attacked by GUN.
Iron Jungle: A base hidden in a jungle. Its filled with shadow androids and is always being attacked by GUN.
Lava Shelter: Eggman's main base hidden deep in a volcano. It seems to be the primary shadow android facility, and has an emergency security system in which the base is flooded with lava except for the center control room.
Egg Fleet: Smaller than in Sonic heroes but same thing, except the flagship is much smaller and resembles a whale.
Aquatic Base: A labratory abandoned ten years ago by scientists. Taken over by Eggman. The launching point for the Egg Carrier 3.
White Acropolis: In greek, acropolis mean "Large City on The Mountain" White Acropolis is a giant base on a mountain thats always in a blizzard.
Egg Carrier 3: A smaller, more sleeker Egg Carrier with less weaponrey and faster speed. Its only flaw seems to be in its engines malfunctioning.
Radical Train: A large train with electronics and heavy armor. not much here.