Chryse Guard Security's Third Group consisted mainly of "Human Debris" and orphaned drifting children with little to no formal education. These children were divided into different task types; the physically fit ones became Mobile Worker pilots while the rest were assigned to pile sandbags or install and remove landmines for practice.
In Post Disaster 323, CGS was hired to escort Kudelia Aina Bernstein to Earth, but on the night of Kudelia's arrival, Gjallarhorn assaulted CGS' base. In the midst of the attack, members of the Third Group discovered that the First Group had deserted them. Prepared for this treachery, Third Group's leader Orga Itsuka had planted remote flares on First Groups' Mobile Workers beforehand, and launched them to lure away Gjallarhorns' Mobile Workers and reduce Group Three's casualties, only to have three Gjallarhorn's Grazes arrive on the battlefield. After Third Group's Mikazuki Augus overwhelmed the Gjallarhorn forces in Gundam Barbatos and killed the Grazes' team leader, the survivors of First Group returned to HQ to punish Third Group for selling them out to Gjallarhorn, and to re-organize themselves in the wake of CGS' president Maruba Arkay disappearing during the commotion. Angry over the pointless deaths and constant mistreatment of the personnel in CGS, Orga instigated a mutiny by having the First Group drugged during dinner and tied up. After waking up, Mikazuki shot and killed First Group's leader Haeda Gunnel and officer Sasai Yankus. Orga then gave everyone else in the First Group the option to either stay and pledge loyalty to the new management or leave with a severance pay. The decision on giving out severance pay was to keep the group's reputation intact. After that, the remaining members formed the current "Tekkadan".
With analysis from CGS' accountant Dexter Culastor, it was discovered that Maruba ran off with majority of the organization's funds, leaving them with less than three months of financial support. Kudelia offered to continue supporting them financially through Nobliss Gordon, one of her sponsors. Aside from the Gundam Barbatos, a Graze Custom, and a handful of Mobile Workers, Tekkadan acquired the CGS' armored assault ship Will-O'-the-Wisp and rechristened it Isaribi. To help Tekkadan get to Earth safely, they hired a local transit company: Orcus Company, but were unaware that the latter were planning on betraying Tekkadan to Gjallarhorn for their own shipping lane protection.
Encounter with Teiwaz
During their journey to escort Kudelia to Earth, Tekkadan was ambushed while in-transit from Mars to the Isaribi by Gjallarhorn inspectors McGillis and Gaelio, Tekkadan was successful in repelling the attack thanks to the efforts of Mikazuki and Akihiro and their Mobile Suits before docking with the Isaribi. Without Orcus Company, Tekkadan was left with little-to-no-way of safely delivering Kudelia to Earth past Gjallarhorn unless they found a way to appease another such delivery company: Teiwaz, stationed in the Jupiter Sphere and holding a great influence on Earth and possessing weaponry that rivaled Gjallarhorn. While deciding a way of negotiating with Teiwaz; Isaribi was hailed by Maruba Arkay; the defunct president of the original CGS who demanded the return of his property. Maruba was shown to be working with Naze Turbine, the manager of the transport branch of Teiwaz and was high-up in the organization. Naze promised Maruba to solve his Gjallarhorn problem along with re-acquiring his ship and property taken by Tekkadan, and refused to negotiate around helping Tekkadan in their current job on the basis of stealing from CGS, leading to Orga and Naze initiating a sortie with Mobile Suits.
While Mikazuki in the Barbatos and Akihiro in the Graze Custom to intercept Nazes' MS force, Tekkadan took the next step: Eugene, in control of the ship, provided smoke screen to allow Orga, Shino, and Dante, to board Naze's ship the Hammerhead and confront Naze and Maruba in person. Arriving on the bridge, Orga walks towards his former employer, ready to kill him for justice on his comrades dying pointlessly by Gjallarhorn, before Orga pulls the trigger Naze says that he has re-considered his deal with Maruba (earlier Maruba told him that he forced all the children in his employ to undergo the life-threatening surgery required to operate the Alaya-Vijnana System, showing little concern for their well-being despite the life-threatening nature of the process), and is now willing to listen to what Orga and Tekkadan have to say, cancelling the sortie between his MS Pilots and recalling them to the Hammerhead for discussions with Tekkadan. This eventually placed Tekkadan in contact with the leader of Teiwaz, and after a Sakasaki ceremony with Naze, made Tekkadan an affiliate of Teiwaz through Naze. This also allowed Tekkadan to receive equipment resupply and upgrades, including a further refinement for the Graze Custom and restoration of Gundam Barbartos to its state during Calamity War.
Encounter with Brewers
Tekkadan then made its way to Earth through the Shoal Zone. In there, they encountered Brewers, a pirate organization. After a grueling battle between the two forces, Tekkadan eventually boarded and captured the Brewer's ship, and receive the spoils of all their ships and mobile suits. While the majority of the spoils were sold for profit, Tekkadan retained the ASW-G-11 Gundam Gusion and refined it to ASW-G-11 Gundam Gusion Rebake.
Riot at Dort Colony
When Tekkadan arrived at Earth Sphere, they stopped at the Dort Colony to deliver a shipment as well as resupply. Due to mechanization of Nobliss and Giliahorn, they were forced to defend their client and themselves as riots broke out, while Gjallarhorn attempted to wipe them out and capture Kudelia, manipulating the media to paint them as villians. Fortunately, Kudelia is able to conduct a broadcast, which forced Gjallarhorn to back off, except for Outer Earth Orbit Regulatory Joint Fleet, whose leader, Carta Issue, decided to pursue Tekkadan.
Meeting with Makanai
Making their way to where Makanai, the former Prime Minister of Arbaru, was exiled, Tekkadan received an additional mission: delivery of both himself and Kudelia to Edmonton, the capital of Arbrau. Their mission was made difficult by the hounding of Outer Earth Orbit Regulatory Joint Fleet, which results in the death of Biscuit Griffin, one of the inner circle of Tekkadan. Still, they successfully chased Issue's force away from the island, allowing Tekkadan to arrive at Alaska, where they continued their journey on trains. En route, they were further stopped by Issue and her remaining forces, but Tekkadan succeed in destroying her force and killed Issue.
End of First Mission
Arriving at Edmonton, they entered a battle of attrition with the Gjallarhorn force stationed there for three days. Although they were outnumbered by Gjallarhorn, Tekkadan managed to hold their grounds, but they are running out of time as the election for the next prime minister is to take place at the afternoon of their third day of battle. In desperation, Tekkadan decided to take a convoy of mobile workers straight into Edmonton, while using the remaining forces and the withdrawing troops as bait. With the mobile suit engaging the Gjallarhorn's Graze, the remaining force engaged Gjallarhorn on the bridge that leads to Edmonton. Help later came in the form of Eugene and Chad's mobile worker group, allowing Orga's convoy to sneak into the city through the dried river bed. A cause celebre emerged when EB-AX2 Graze Ein entered the city limit, allowing Barbatos to follow it and engage it, ending with destruction of Graze Ein, while Gaelio Bauduin was defeated by Montag in his V08-1228 Grimgerde. With the successful delivery of Makanai and Kudelia to the parliament, the two were able to bring about a political victory that caused a lost in trust in Gjallarhorn, while making Tekkadan a respected company.
After two years, Tekkadan expanded significantly; they became a direct affiliate of Teiwaz. An Earth branch was also created, which served as the military advisor for Arbrau. Tekkadan was eventually hired by Kudelia to protect her during a half metal mine visit. During the mission, they fought with the pirate group, Dawn Horizon Corps, hired by Terra Liberionis, whose leader was upset with Kudelia's refusal to help him. Although the attack was repealed, Tekkadan had became the target of the pirate group. Tekkadan then went into space and fought with the pirate group. WIth help from a Gjallarhorn force lead by McGillis Fareed's subordinate, Isurugi Camice, Tekkadan defeated the group and captured its leader. When McGillis went to Mars later, he proposed an alliance with Tekkadan, and Orga agreed.
The Earth branch was then dragged into a war between Arbrau and SAU, which was secretly instigated by Gjallarhorn's Lord Rustal through Galan Mossa, a mercenary that worked for him, in order to weaken McGillis' power base. The situation was made worse as the Earth branch auditor Radice had colluded with Galan, and interfered with communications between Tekkadan's Mars HQ and the Earth branch. Eventually, Radice's betrayal was exposed by the arrival of Mars HQ's force, leading to his execution by Substitute Commander Takaki. Following the conclusion of the SAU-Arbrau War, Orga had decided to temporarily disband the Earth Branch and withdraw all assets, mobile suits, and personnel to Mars. After being offered complete control of Mars in return for supporting him, Tekkadan joins in McGillis Fareed's revolution against the ruling system of Gjallarhorn.
After McGillis Fareed's coup forces are defeated by the Arianrhod fleet, Tekkadan retreats to Mars with the enemy in pursuit. Tekkadan's Mars HQ was eventually surrounded by the Arianrhod fleet. While Orga offered to surrender McGillis to Rustal in exchange for clemency, Rustal refused as Gjallarhorn had to make Tekkadan a scapegoat to be viewed as an effective peacemaker. With Arianrhod blocking all forms of communication to the outside and the media manipulated to believe Tekkadan refused to surrender, It seemed all hope was lost. But a blocked tunnel underneath the base was found that could allow them to escape to Chryse and members of the organization started to dig their way out. Meanwhile, Orga Itsuka with a few members sneak past the enemy and head towards Admoss Company where they contacted Makanai for help. Makanai and former members of Turbines were willing to help them escape to Earth where they could forge new identities. However, Orga was killed by Nobliss Gordon's men as he left the company. In order to give the non-combatants time to escape, Mikazuki, Akihiro, Eugene, and Hush lead a team of mobile suits against the Arianrhod fleet's massive attack force. After a long and brutal fight, Eugene and a large number of Tekkadan personel manage to escape via the unblocked tunnel. Unfortunately, Mikazuki, Akihiro, Hush, and Elgar are all killed in battle. With the defeat of Tekkadan's Gundams and the organization's base wrecked, it seemed to the public that Tekkadan had been wiped out.
Post McGillis Fareed Incident
Years after the disbandment of Tekkadan, many former members work now for Kudelia, who has risen to lead the new independent Martian government, or for Nadi Kassapa at his mobile worker factory. After learning Nobliss Gordon has returned to Mars, Ride Mass and several former Tekkadan members went MIA to assassinate the former to exact revenge for Orga Itsuka. A memorial stone with names of Tekkadan's deceased remained on the outskirts of Sakura's farm.
Their main headquarter was based on the outskurts of the Martian City of Chryse; Their Earth branch was formerly headquartered at the outskirt of Edmonton. Both fall under the juristriction of Arbrau.
As of the beginning of Season 2, Tekkadan was organized as follow:
- Commando Unit
- Mikazuki Augus (Unit Leader)
- 1st Working Unit (aka Ryusei Unit)
- P.D 325
- Lux Leloufa
- Tori Thaulow
- Aston Altland
- Gary Pilaw
- Peter Wovan
- Lang Fei
- Tikkes Camus
- Kandya Valach
- Leblonde Frounde
- Rita Reroutata
- Lamy Gress
- Ugurus Acaslislo
- Marg Tartich
- Jieming Long
- Boris Keijin
- Meer Sels
- Colin Marley
- Radice Riloto
- Norba Shino
- Orga Itsuka
- Hush Middy
- Akihiro Altland
- Mikazuki Augus