Great Dome

Located in Iacon, the Great Dome is the city-state's center piece. Sometimes, it outlines Iacon Central and provides protection to the Celestial Spires, where the government of Iacon is seated. Other times, the Great Dome functions as the main Autobot base on Cybertron. Because Iacon tends to be the place that the Autobots protect best, the Dome and the Spires are of symbolic importance to them and they often refer to them to signify amazement, surprise or exasperation.

The Transformers cartoon
Iacon served as the headquarters of the Autobots under Optimus Prime's command. Access to the base was only possible by an extendable bridge and the Autobots needed to signal their approach before being allowed into Iacon. Among the facilities the base contained was a launch bay on the highest floor; the roof could be retracted to allow a starship to leave.

As the conflict dragged on, energy became scarce and much was invested in simply gathering what was still around. When that strategy reached its dead end, the Autobots decided to take a starship and look for energy off-planet. The Decepticons learnt of this plan and dispatched the duo of Soundwave, whose altmode resembled the lampposts in front of Iacon, and Laserbeak to Iacon to keep tabs on the Autobots. When the Autobots prepared for takeoff, Soundwave reported back to Decepticon Headquarters, where his faction had prepared the launch of a starship of their own. They took off mere moments after the Autobots did.

Four million years later, the Dinobots traveled to Cybertron and were captured by Shockwave's troops. The only one to escape was Swoop, who flew away from Decepticon Headquarters and kept on flying until he had passed Iacon, which was in the same pristine state as the Autobots had left it in.

Alternatively, the Autobots prepared to launch their starship while Iacon's surroundings were burning as a consequence of a Decepticon assault. Optimus Prime was the last one to enter the vessel, but was momentarily halted by the arrival of Elita One and her soldiers, who wanted to board as well. Optimus Prime denied their request, stating it was totally safer to stay in the base while the Decepticon forces attacked it too dangerous. The words had barely left his mouth when Iacon was bombarded and missiles got in through the open roof, seemingly killing Elita One and the others. Though the starship also took some hits, the launch could supposedly proceed as planned.

The Headmasters cartoon
When Cybertron was reconquered by the Autobots in 2005, Autobot Base was taken in use again and sometime thereafter upgraded with a space bridge port. In 2011, Spike Witwicky and Carly were having tea inside Autobot Base when the base's alarms flared up due to a grand scale Decepticon attack on the planet. They, the Technobots, the Dinobots, Wreck-Gar, Blurr and Kup gathered at the control room to get the details of the situation. While the Dinobots and Technobots were sent outside to fight, Spike contacted the Athenia base to ask Optimus Prime for reinforcements. Prime acknowledged his request and suggested that he come to Athenia where it was safe. Spike agreed that was the best course of action.

However, he, Carly and Kup didn't leave immediately, as Spike wanted to understand what the Decepticons were after. He eventually realized the Decepticons intended to reprogram Vector Sigma into serving them now that it had been set to neutral with the depletion of the Matrix. The trio wanted to contact Optimus Prime to tell him this, but Wreck-Gar warned them the Decepticons were attacking the space bridge, so they opted to hurry and tell Prime in person when they'd arrive at Athenia.

The only problem with that plan was that Optimus Prime had already gone to Cybertron by the time they arrived at Athenia and there was no way to reach him. The arrival of the Headmasters opened an opportunity to get the information delivered, as Fortress decided to go to Cybertron to help Optimus personally. Arcee, Kup and Blurr went with him, but stayed within Autobot Base to monitor Vector Sigma.

Much later, during another a grand scale attack on Cybertron by the Decepticons to obtain the cybertonuron, Rodimus Prime, Fortress, Arcee, Blurr and Kup got together around a digital map to observe the way the fight was going and decide how they could battle more effectively. Fortress went out to help the troops, while the rest joined Wheelie and Daniel in the control room to deal with the battle logistics. However, Fortress and the other Headmasters arrived about an hour after with the message they had to get off Cybertron, as it would explode within ten minutes and nothing could be done to prevent that. Rodimus Prime ordered the troops to evacuate. He and the others at Autobot Base were the last to leave, fifteen seconds before Cybertron ceased to be.

Marvel The Transformers comics
''When the Decepticons launched their assault on Iacon, the Great Dome protected the Spires and the Autobots within from the violence. The Council of Autobot Elders held a hearing inside the Celestial Temple on how to solve their predicament and Xaaron's wish to grant Optimus Prime full control of the Autobot army was agreed to. Meanwhile, Optimus Prime had sent out Bluestreak and Fusion to get shatter bombs from across Iacon. Fusion perished along the way, but Bluestreak made it back to the Great Dome safely with the bomb. Xaaron then informed Optimus Prime about his new authority, the latter glad he could now continue his plan to force the Decepticons into retreat with the approval of the Council.''

''As the war continued and Cybertron was knocked out of its orbit, an asteroid belt threated to destroy the planet. Optimus Prime and several other Autobots board a ship to reach and destroy the asteroids, but the ship and its crew were lost. Despite losing their finest soldiers, the Council managed to organize the remaining Autobots in a force that could still withstand the Decepticons' attempt to take over Iacon. This situation remained for hundreds of thousands of years, until Decepticon leader Trannis decided that utterly destroying Iacon would do just fine too.''

As the only surviving Council member, Xaaron became one of the Autobot resistance's leaders and set up his base under the remains of the Celestial Temple, within the still somewhat protective cover of the Great Dome.

In the meantime:

"By Iacon's Great Dome" was Prowl's response to learning that there was a high density thermo-nuclear bomb inside Autobot Headquarters.

''This was followed up with a "By the Great Dome!" when the high density thermo-nuclear bomb-carrying Guardian was standing right on the other side of the door.''

Trailbreaker reacted with a "By Iacon's Great Dome" when the military base in Black Rock Desert exploded.

Upon seeing the Vrobians' true appearance, Backstreet let out a "By the Great Dome of Iacon!"

As a Matrix-obsessed Thunderwing came running towards him, Bumblebee exclaimed: "By the Great Dome!"

Shattered Glass
Iacon was the main complex in the city-state of the same name. It served as the headquarters of the Autobots and was home to some of them, among which Optimus Prime. Characteristic lampposts adorned the entrance to the complex. Facilities contained within Iacon included a smelting pool as well as a crusher device for those times the smelting pool was not an option.

Optimus Prime and a number of his soldiers had prepared a relaxing session of dumping Decepticons in the base's smelting pool when they were contacted by Rodimus. The big news was that he had found Cliffjumper, Optimus's friend who had been presumed dead, and Optimus interrupted the smelting session so he could personally welcome back Cliffjumper at the door. Optimus Prime was beside himself to see his good friend alive and led him through the base's main hall, which he had recently redecorated with Decepticon corpses, to the smelting pool chamber to celebrate his return with some torture. By this point, Cliffjumper had seen and heard enough to start speaking up against this violent behavior of "his" comrades and was promptly shot down for his effort. Rather than killing him, Optimus Prime ordered that he be dumped in the Rad Zone so that he could try and prove he still was worthy of calling himself an Autobot.

Some time later, Optimus Prime had Blurr and Goldbug report to him in the combat training room. While Optimus went through hard light battle program zeta, the two Autobots reported on the status of the Ark project. They might as well not have bothered, as Optimus denied or mocked any negative elements in the report. That would not be one of his smarter moments.

Following a painful defeat that resulted in the loss of the Arch-Ayr fuel dump to the Decepticons and the loss of the Dinobots, Optimus Prime summoned Blurr and Side Burn to his throne room to find a suitable course of action. Eventually, it was decided to hunt for whichever Dinobots they could find and that Wheeljack, who had built the Dinobots but failed to control them, would not be sent back in exile, but put to work repairing the Ark. In the end, eight Dinobots were captured, but Blurr and Rodimus returned with the news that Grimlock, who was of most interest to Optimus, had perished. Optimus had both suitably punished, but Blurr was partly spared because, just as Optimus was reaching the peak of his anger, Grimlock came sauntering into the base. Claiming his sovereignty but offering his loyalty, the prime Dinobot joined the Autobots and made Optimus less angry enough that the Autobot leader took out the rest of it on an inanimate object rather than Blurr.

When the Autobots captured the Decepticons Dreadwind and Darkwind, they had them executed by dropping them into Iacon's smelting pool. Some time later, Optimus Prime was watching the news when it reported that Megatron had been killed by a Decepticon traitor. Enraged that it had not been he who got to kill his nemesis, Optimus threw the television out of his chambers' window. This was recorded by the cameras the news network had placed outside Optimus's chambers in anticipation of his reaction. Understanding that he had been the messenger of the worst possible news Optimus could have learned about, news anchor Rook decided to skip town for a while.

Knights of Unicron
Iacon Stadium was the twenty-sixth and final venue for the Knights of Unicron on their 2014 "Till All Are One" tour.

Foreign names

 * Japanese: Autobot Base (サイバトロン基地 Cybertron Kichi)
 * English: Autobot Headquarters (Shout! Factory sub)