This battle takes place when RK-4 decides to help out the KSA agents in their fight against Cerberus. Ked tracks Sangeen down with Lutai, who later engages in a battle against Tao and Takeo (see to Tao & Takeo vs Lutai).
After Sangeen is defeated by Ked, the RK team comes to his rescue. Sangeen opens his eyes to see M-21 by his side, telling him to move quickly. The two flee and Ked chases after them.
M-21, Tao & Takeo vs Ked
Ked mocks them for being too slow and Sangeen urges M-21 to flee without him since he's responsible for slowing them down. Tao directs Takeo to support M-21, who then shoots bullets, which penetrates Ked's leg. Ked quickly stops to realize that Sangeen has even more teammates and becomes enraged. Tao then tells M-21 to surprise Ked: M-21 jumps up and speeding downwards at a blistering speed with his claws, strikes Ked, who is caught by surprise.
Sangeen admires M-21's powers and asks M-21 whether he was always able to use strength like this but M-21 dismisses the compliment, telling him to move. Sangeen then realizes that Ked isn't defeated.
Ked jumps up from the rumble, having received minor wounds. Ked hates being unable to find his opponent's identity as M-21 has masked his face but is entertained by M-21's abilities - superior to Sangeen's, M-21's attack has actually hurt him. M-21 asks Sangeen to flee but Ked tries to obstruct him. However, Ked is stopped by M-21, who aims his claws directly towards his face, and just dodges the attack. Ked punches the air towards M-21 but his movement is distracted by Takeo, who shoots his arm. Then, M-21 takes the opportunity to slash Ked multiple times. Ked can do nothing but just block the attacks. He tries to attack M-21 but then his movements are distracted again by Takeo. Tao then tells M-21 to never let his guard down but rather use the opponent's rage and his underestimation of Takeo's bullets, which have been crafted by Tao himself and Frankenstein (to damage the opponent's nerves). Ked pounces at M-21 with his fist aimed towards him but then just as Tao predicted, Ked becomes enraged after being hit by Takeo again. Tao is proven correct on Ked's downfall in battle ability due to his rage, Takeo's bullets slowly building up the damage and M-21's main attacks all working towards their advantage. Ked decides to ignore these bullets now and this reminds the trio of Rael. Ked jumps up and smashes the ground M-21 is standing on, but the RK member evades. M-21 starts to back away while taking hits from Ked's continuous punches directed towards him. Then, Ked falls into the trap and Tao activates the electric zone to electrocute and freeze on the spot. M-21 pounces at him, aiming to slash him from above, while Takeo shoots him. Ked has to take the hit from Takeo while blocking M-21's attack. Ked then loses his temper and throws his fist with some aura at M-21 but he ends up punching the wall instead and getting shot at more by Takeo as M-21 dodges his punch. Through the dust cloud, M-21 comes from above, aiming his claws at Ked, who moves to parry the attack with his fist. But then, he is shot by Takeo on the chest which effectively stops him. M-21 does his best and slashes him with all his power and Ked takes the hit straight on.
M-21 lands on the ground nearby and Ked crashes out of the rumble, having transformed into his true form - revealing the body suit. The guard trio are irritated by this and realizes why Dr. Aris never believed that the whole DA-5 could take on a single member of Cerberus. Then Tao is found by Lutai, who left to look for who was giving support to Sangeen and M-21. Tao contacts M-21 and Takeo, reporting that he has been located due to his carelessness and that he will have to abandon their communication in order to concentrate on his own battle.
M-21 & Takeo vs Ked
The transformed Ked attacks M-21 at an amazing speed and power, who just manages to block the beam. Takeo's bullets could not penetrate Ked's body suit at all and through the dust, M-21 pounces at Ked, who is by contrast rather relaxed about the situation. He smiles and throws a massive punch directly at M-21's abdomen, sending him flying and smashing into a nearby building. Takeo decides that he cannot attack at long distance any longer and travels to the scene. Meanwhile, Sangeen finds Yonsu and the two of them decide to go to the battle scene as well.
The dust clears and Ked asks M-21 who walks out with wounds, to be as arrogant as previously. Ked is glad to see that M-21 isn't defeated yet and punches at him. However, M-21 dodges the attack and instead attacks him from the side. Ked blocks the slash but is surprised to see that M-21 is able to make a scratch on his real body. But then, Ked turns around to smash M-21 on the jaw, who helplessly ends up flying again. Ked jumps up mid-air to ruthlessly punch him multiple times on his abdomen and then throws him smashing onto the ground. He follows up and spears M-21 into the ground with his weight. M-21 coughs blood but slashes at Ked, who jumps away from M-21 with ease. Ked is impressed that M-21 is able to fight back even after getting beaten so severely.
Takeo tries to contact M-21 but then realizes that his communication device may have been destroyed during his battle. He then hears a different explosive sound and predicts that Tao may be fighting there. When he is caught in dilemma, struggling to choose which of his friends to help, he gets a message from Regis to go and help out Tao.
Regis & M-21 vs Ked
Ked decides to bring about the end of M-21 but then he swiftly dodges a blast from Regis, who enters the battle scene and apologizes to M-21 for being late.
Ked is surprised to see another masked opponent, however, Regis completely ignores him and asks M-21 whether or not he can still fight. M-21 is convinced that he can still fight and Regis sees no point in trying to persuade him to rest. Ked becomes even more irritated as the duo completely blank him out. Then Regis tells him to shut up and stop complaining as he can find not even the slightest elegance from him. This comment causes Ked to rage and he swings a gigantic punch at the duo.
The duo dodge the attack and counter with team effort. Ked is caught behind his back by Regis. He turns around just in time to save himself with a block. M-21 lunges from behind to slash Ked's leg, which hurts him quite a lot. In retaliation, Ked turns around to smash M-21 but Regis saves M-21 just in time sending a punch to Ked's face. Regis sends an energy beam to follow Ked, who is flying backwards but Ked manages to deflect the beam with his fist. With his arm up, Regis manages to smack Ked's side, causing the Cerberus armor to crack and when Ked is just about to punch Regis, he falls onto his knees after M-21 slashes his back. Regis times his attack well to smack Ked's abdomen with force and then elbows his face. Ked violently bounces away and smashes into the floor. Regis remembers Karias' advice to him during their training sessions and thinks of him in gratitude. Ked is extremely ashamed of himself and lets out a scream, radiating vast amounts of energy and he throws a wave of punches at the duo. This shocks M-21 and Regis, who manage to dodge the punches and whilst Ked swears to kill them both, he is slashed from both ways by the duo and after a loud explosion, Ked smashes into the ground, defeated.
Regis and M-21 are mistaken in thinking that they are victorious as Rodin, Ked's teammate, arrives at the scene.
Regis & M-21 vs Rodin & Ked
Rodin reveals that the 12th Elder is on his way which greatly shocks Ked. In order to avoid any embarrassment, Rodin decides to end this quick and attacks the duo.
After much dodging and taking hits from Rodin, Regis is worn out. Rodin shoots three energy beams at Regis, who just manages to deflect the blasts to the building behind him, whilst taking some damage. However, he is shocked to see another energy beam following up immediately and while he dodges the beam, he is distracted at the sight of M-21 being smashed by Ked. Rodin takes the opportunity to smack Regis in the side with his spear and sends him flying. Meanwhile, Ked has smashed M-21 into the ground and constantly punches him. M-21 curses his luck for being unable to finish him off as his physical conditions are similar to Ked's current condition: both are appalling.
Assistance from KSA agents
Suddenly, Ked takes a blast on the back and he turns around viciously to see Yonsu kicking an energy beam at Ked. He blocks it with relative ease and lunges at her. He blocks another of her kick with his right arm and throws a punch at her with his left fist. Yonsu manages to dodge the attack and she realizes what kind of a monster she is facing. She stares at M-21 in disbelief (as he faced Ked) but she is caught off-guard as Ked nears his huge fist at her face. However he is stopped by M-21, who collapses again after slashing Ked hard on the back. Ked coughs blood and collapses too.
Ked cannot move and Yonsu cannot believe what she has just seen. Rodin expresses his disappointment at Ked. Rodin turns his attention to Yonsu and after receiving a blank reply, saying that KSA is not associated with the duo, Rodin believes it to be a lie and decides to find out by force. He swings his spear at Yonsu, who dodges only to find herself in deep trouble as their differences in strength is too great to overcome with luck. Rodin spins his spear and then jabs at her; she manages to dodge it but Rodin shows great control over his weapon as the spear suddenly changes poles to smash Yonsu's face. Still recovering from the blow, even though her reactions saved her from further damage, Yonsu sees a charging Rodin with his spearhead aimed at her face. She remains helpless until Sangeen comes to her rescue by throwing energy projectiles at Rodin. However, he sees the attack and blocks it with ease. After brief discussion, Sangeen gives his wife the signal by attacking Rodin. Rodin stares at the projectiles as they strangely disappear but he sees that that attack was a trick as Yonsu aims a huge kick at him from above. The couple believe that he must be wounded but Sangeen is unable to react to a sudden throw of the spear and smashes into the building behind him. Yonsu screams for him only to take a blow as well which sends her flying.
Regis vs Rodin
The two Cerberus agents chuckle only to see that Regis is still able to fight. Regis gathers up all the remaining aura he has and charges at Rodin. They are surprised to see that Regis still had substantial amounts of energy left in him. He suddenly speeds up and uses mind control to temporarily stop Rodin. The duo collide and after a huge explosion, Regis pants in fatigue whilst Rodin stands silent, caught in shock. He sees that parts of his armor are torn and attacks Regis in fury. The attack is barely blocked by Regis, who finds a huge spearhead aimed at his face. However, Rodin is stopped by Taze.
The 12th Elder and Taze stand before Ked and Rodin. Taze rebukes her two subordinates harshly for getting wounded against Crombel's inventions and punishes them both. However, she becomes further enraged by M-21 and Regis and attacks them; Regis doesn't hold back and she asks the Elder whether she can kill him, to which the Elder concurs. Taze throws Regis up in the air and sends a huge energy blast at him; as the dust clears, everyone is shocked to see Seira holding Regis, whilst looking unaffected by the attack. Raizel and Frankenstein also follow up from behind. From here, Seira decides to silence Taze so that Frankenstein can investigate the relationship between the 12th Elder and Roctis Kravei.