Hades City

Hades City (ハデス市 Hadesu-shi) is a stand alone floating landmark that appears in Beyblade Metal Masters episode 50. Shaped like a spinning top, Hades City was built by Dr. Zigguart in order to utilize Faust as his personal right hand blader from the Arrangement, gathering blader data from the World Championships to construct the perfect Bey, Basalt Horogium 145 WD. The Bey in return, fuels Hades City to hover over Metal Bey City like an exotic UFO, thanks to it's special move, Spiral Dimension.

The city mainly is plotted with scattered generic city buildings, a tall tower accumulated with nuclear energy centering the middle of the circumference.

The Perfect Blader
In the hands of Hades Inc, Toby's potential as a Beyblader took the mad doctor Ziggurat's eye. He cured Toby's illness using the Arrangement System which unlocked Toby's potential as a Beyblader, but to keep him under his watch Ziggurat hypnotized Toby into an alter ego called Faust.

Faust was the perfect Beyblade of Hades Inc and was chosen to power the ultimate energy system. This energy system would be fueled by Faust's partner Beyblade, Twisted Tempo. This energy source would fuel the ultimate weapon known as the Spiral Force. Faust's only job was to use his powers to spin Tempo and power the machine but was interrupted when his former friend Masamune and Masamune's partner Gingka arrived to stop him.

Faust easily dominates the both of them in battle but because of an outside interference to the Spiral Force. The shock released causes all three of their Beys to stop spinning. With the spiral force stopped momentarily, Gingka moves to stop the energy fueling it while Masamune tries to free Toby's mind.

Faust battles Masamune, easily able to defeat him and nearly does so until Zeo arrives to help. Faust uses his powers to control time and space with the energy to travel through his memories. In these memories, Zeo and Masamune remind Toby of who he is, and frees his mind of "Faust". With the Spiral Force stopped and Toby free and healed, they all return home to the Dungeon Gym.

Trivia

 * Hades City shares similar appearance with Final Fantasy VII's Midgar, the Spiral Dimension Tower as a stand piece in relation and reference to the Shinra Mako Reactor Tower. This also ties in with Takafumi Adachi drawing heavy inspiration from the game, making Dr. Ziggurat own an incorporation and trait identical personalities in reference to Rufus Shinra.
 * Hades City is the second floating landmark in the Metal Fight Beyblade series. The first to appear was the Space Ark owned by Helios and his grandfather from the Sol Blaze movie.