Mt. Mobius

The Veg-O-Fortress, Robotnik's base on Mt. Mobius, seen in the opening to Sonic Spinball.

Mt. MobiusMedia:SonicSpinball MD US manual.pdf is a location that serves as the setting for Sonic the Hedgehog Spinball. It is a titanic volcano rising up out of the sea and being generally intimidating to nearby observers.

Mt. Mobius can also be seen in the world map for Sonic Origins, representing the Mission and Story modes.

Veg-O-Fortress

Sonic the Hedgehog floating in the Toxic Caves.

What Mt. Mobius looked like in its pristine, natural state is never shown, for the mountain makes its first appearence only after the Veg-O-Fortress is built on it by Dr. Robotnik. In the style of evil geniuses everywhere, Robotnik decides that the highest point in the world would provide an excellent site for another of his evil bases; and the locale is all the more attractive due to the fact that Mt. Mobius' furious volcanism will provide ample electricity for his deranged schemes.

Thus, by the time Sonic and Tails arrive, the towering spire of rock has been mechanised into the Veg-O-Fortress. This industrialised leviathan includes four distinct levels:

• Toxic Caves (Toxic Pools in the 8-bit versions): Sonic is flushed into a stinky cavern full of toxic sludge and mine carts, which just so happens to be the place where Robotnik dumps all of the industrial waste.
• Lava Powerhouse: Sonic ascends to the next level, a power station of sorts that uses magma and steam energy to run various machines.
• The Machine: At the industrial heart of the Veg-O-Fortress lies an immense, automated Badnik production plant, complete with mass-robotizer and a central prison for the animals that are yet to be 'processed'.
• Showdown (Final Showdown in the 8-bit versions): A launch pad at the summit of the mountain, where Robotnik attempts to escape aboard his spaceship.

The Veg-O-Fortress' main form of defense is the Pinball Defense System, a gigantic network constructed like a giant pinball machine built with the intention of stopping Sonic from stopping Robotnik's schemes. Placed all around the Veg-O-Fortress are the Chaos Emeralds, which stabilise the volcano on which the fortress stands. Without the Emeralds, the volcano will erupt and destroy the fortress.

Destruction

After pretty much everything inside the Veg-O-Fortress gets wrecked and the Chaos Emeralds are taken during the events of Sonic Spinball, Robotnik's facility collapses. The end sequence of the game shows Mt. Mobius and the remnants of the Veg-O-Fortress falling beneath the waves. Consequently, the mountain is destroyed.

In other media

Adventures of Sonic the Hedgehog

Mt. Mobius appears in the Adventures of Sonic the Hedgehog episode Big Daddy, where Dr. Robotnik plots to install the most powerful laser cannon ever built on the top of the never before climbed mountain.

Dr. Robotnik's Pinball Fortress appears in the episode Attack on Pinball Fortress, a loose adaptation of Sonic the Hedgehog Spinball. The Pinball Fortress is based upon the Pinball Defense System of the video game, though it isn't located on Mt. Mobius. It houses the Toxic Pools and Robotnik's robot, Boss Scorpion.

Sonic the Hedgehog (Archie comics)

In the Sonic the Hedgehog comic series by Archie Comics, Mt. Mobius and the Veg-O-Fortress were both featured in issue #6 as the comic's first video game adaptation. Sonic would locate the volcano and blast his way through the Pinball Defense System while avoiding the many traps, robots and pitcher plants, only to fall for a trap set up by Dr. Robotnik, resulting in him being ejected from the volcano by a hidden spring.

Later, in issues #86 and #87, Metal Sonic would imprison Tails within Mt. Mobius as an attempt to exact revenge on Sonic. As the volcano erupted, Metal Sonic would ultimately save the heroes from the eruption at the cost of his own life.

Sonic the Comic

Mount Mobius is mentioned in Sonic the Comic issue #24's The Sonic Terminator, Part 1. It is said to be the location of Dr. Robotnik's Badnik processing plant, the Veg-O-Fortress, where the captured Freedom Fighters are to be transported. However, the Freedom Fighters are rescued by Captain Plunder and his crew, and neither Mount Mobius nor the Veg-O-Fortress are ever mentioned again.