Citadel Robotnik was the centre of operations for Doctor Robotnik, in the last years of RBR. Located in the Metropolis Zone, the Citadel was the representation of the Robotnik Empire until Sonic the Hedgehog's final victory in the first war. Robotnik was given a better view of his people from the Citadel than the Death Egg and Egg Fortress ever did.
Robotnik originally lived in the Special Zone, ruling Mobius from his Egg Fortress. Needing to be closer to his citizens, he launched a new Death Egg, until that crashed on the Floating Island, making the Launch Base Zone his new home. When his new plan failed, Robotnik moved his operations to the Metropolis Zone, building a massive building in his image - Citadel Robotnik.
The first task at Robotnik's new home was to locate the Emerald Hill folk, wishing to make them suffer after what Sonic did to the Death Egg. Within these walls, Robotnik and Grimer would develop Commander Brutus, Mekanik and even a new breed of Metallix. Even secretary robot Receptionik found a home there. Sonic was first brought to the Citadel by Mr Blobnik, tasked with rescuing Grimer from the Brotherhood of Metallix. He later returned with Porker Lewis and the Chaotix Crew, just in time to save the world from the Metallix Emperor and his followers. Not long after, Sonic returned with the Freedom Fighters to delete important files from Robotnik's database.
Some time later, Robotnik headed to the Floating Island to deal with the Emerald Hill folk, leaving Grimer in charge. The Freedom Fighters saw this as the perfect opportunity to sabotage the Citadel, but found themselves having to rescue the people from bullying Troopers. With a massive riot underway, Amy Rose and Johnny Lightfoot planned to head to the Citadel to use Robotnik's weapons, but found their way blocked by Vermin the Cybernik. Their cause was aided by the electromagnetic pulse which knocked out every Badnik in the Zone and the world. When Robotnik and Grimer eventually returned to the Citadel to power up their weapons and back-up energy, Sonic overpowered the generator, causing the core to overheat and blow up, ripping Citadel Robotnik. With their symbol of oppression in flames, the people of Mobius celebrated V.R. Day.
In the days after Citadel Robotnik's destruction, the ruins were being used as the hideout for the Doctor Robotnik Appreciation Tribe. They were also where Sonic found the schematics for Shortfuse the Cybernik's armour and where Kog was revived. Eventually the remains of the fortress were removed, and the Citadel's moat reformed into the Crystal Ring, a public swimming pool.
Sonic the Comic Online
As part of the New Robotnik Empire, a new Citadel Robotnik appears to have been built near to the coast of the Metropolis Zone. It could be seen when Tails overlooked the city from afar in "Sky Chase".
- Issue 55 and Issue 56 - The Great Escape!
- Issue 58 - The Rampage of Mekanik
- Issue 59 to Issue 61 - The Brotherhood of Metallix
- Issue 63 to Issue 66 - Project Brutus
- Issue 63 to Issue 67 - Cybernik Strikes Back
- Issue 69 to Issue 72 - Brute Force
- Issue 71 and Issue 72 - The Return of Chaotix
- Issue 74 - Mission to the Metropolis Zone
- Issue 77 - Voice of the People
- Issue 78 - Plasma
- Issue 79 to Issue 82 - Revolution
- Issue 83 - Bubble Trouble
- Issue 87 - Mister Shifter
- Issue 92 - Head in the Clouds
- Issue 93 - Season of Goodwill
- Issue 96 - Mock the Doc
- Issue 98 - Solidarity
- Issue 99 - No Exit
- Issue 100 - The Final Victory
- Issue 103 - Crawling From the Wreckage
- Issue 109 - Kog the Mighty
- Issue 259 - Sky Chase