Heroes vs. Psykos and Orochi

They just keep coming. To dare oppose the culmination of my evolution... Foolish inferior life forms!

Heroes vs. Psykos and Orochi is the battle between the heroes Tatsumaki, Genos, Drive Knight, Tanktop Master, Atomic Samurai, Puri-Puri Prisoner, Superalloy Darkshine, Bang, Bomb, and Fubuki against the leaders of the Monster Association, Psykos and Orochi.

Prelude
Tatsumaki is battling the leaders of the monster association, Psykos and Orochi, who have gained the upper hand and have rendered her helpless. The disfigured fusion of Psykos and Orochi prepares to finish her off with a massive energy attack. Just as they launch their beam, it is intercepted by a wave of energy from the ground, which launches both beams into the sky.

Meanwhile, in the distance, Drive Knight and a sedated Nyan watch the battle. Intent on capturing a sample of Psykos and Orochi's flesh, Drive Knight severs an underground power cable to recharge his depleted energy, then heads toward the battlefield.

Battle
Psykos, Tatsumaki, and many spectators watch as a "blue dragon", Genos, circles the tower. Genos uses Thunder Drill Cannon to attack the fusion head-on, but his attack only succeeds in deflecting the fusion's beam. Orochi's dragons attempt to attack Genos on their own, but Genos matches them with his own lasers. Tatsumaki chides Genos for interrupting the battle, but Genos rebuffs her and tells her to finish off the fusion while he deals with the energy beams. He laments having to use his full power so soon, and recalls Dr. Kuseno's warning about his newest upgrade - it can only be used for ten seconds. The two heroes face down the monster as Genos wonders whether they will make it.

Psykos and Orochi proceed with relentless attacks towards Genos and Tatsumaki. Genos finally uses his full-powered attack True Spiral Incineration Cannon, which succeeds in temporarily neutralizing the fusion's beams. This allows Tatsumaki to pull the majority of the heroes on the assault team to safety, except Flashy Flash, Iaian, Zombieman, and Pig God (though the latter heroes arrive independently shortly afterward.)

Unfortunately, Genos quickly fries himself using his own power due to the ten-second limitation and is rendered helpless. Tatsumaki, having made a recovery by then, congratulates Genos on his accomplishments and easily redirects the energy beams fired from the fusion. Using the vast extent of her psychic powers, Tatsumaki manages to suppress Psykos and Orochi while destroying its roots and body by "wringing" it dry. This ability was so powerful that it completely distorted the landscape of Z-City.

As the night begins to set, Psykos and Orochi are nearly defeated. However, due to previous injuries and her usage of a substantially powerful psychic move, Tatsumaki is pushed to her limit. Psykos senses this and immediately utilizes a large smokescreen to temporarily blind Tatsumaki while utilizing what's left of Orochi's destroyed body to create an organic fighter jet. As Psykos plans to absorb the blood and flesh of the city, she copies Tatsumaki's move and creates multiple decoys in order to scatter her presence and escape.

Psykos taunts Tatsumaki about the limits of her power, however, Tatsumaki's psychic power is unfaltering as she creates a double-layered barrier that is completely immune to direction inversions. Due to this, Psykos decides to fire an energy beam at Tatsumaki frontally as such a large barrier would supposedly take up all of her concentration. Unfortunately, the beam only struck a decoy, while also serving to reveal Psykos' current location.

Before Tatsumaki could launch a proper attack at Psykos, Drive Knight interrupts the battle by firing two energy beams in his Flying Chariot form. One of the beams strikes Psykos as she expresses her frustration from the unrelenting attacks, Drive Knight on the other hand seems eager to collect samples of Psykos and Orochi. The chase continues in the air as each side fires multiple energy beams at each other. While Psykos is able to temporarily neutralize or evade all of Drive Knight's attacks, a weakened Genos drops to the ground and quickly explains the situation to the rescued S-Class heroes. He pleads with the heroes to assist in the fight, then gathers himself and returns to attacking Psykos with his own energy cannons.

Atomic Samurai acknowledges Genos' plea and tries to hit Psykos with his Air Blade, but the attack's range is too short. Falling back to the ground, the hero watches Drive Knight, Tatsumaki, and Genos fighting, shocked that the three are actually cooperating. Pig God releases Iaian, Zombieman, and the unconscious members of Narinki's Private Squad from his mouth, revealing that he had rescued them on his way to the surface. Tanktop Master, noticing the severity of the fight from afar, also decides to head to the scene. As the heroes on the surface regain composure, Bang, Bomb, and Fubuki arrive, much to the surprise of the S-Class heroes. After some misinformation is cleared up by Child Emperor regarding Bang's status, Fubuki notices that Tatsumaki is losing consciousness. She begs the S-Class heroes to take action and join the battle.

A half-conscious Tatsumaki kneels on the eerie tower she created by twisting Psykos and Orochi. Even though she's at her limit, she manages to hold up the psychic barrier to keep Psykos from escaping. Struck against the barrier by Drive Knight, Psykos quickly realizes that her main objective should be to kill Tatsumaki. She proceeds to fire several missiles but they were intercepted by Drive Knight's Bishop form and Genos before they could reach Tatsumaki. Genos notices that Tatsumaki has finally lost consciousness.

Tatsumaki begins to have a flashback 18 years ago in some research settlement. Due to a hybrid monster sample going rogue, the owner of the research settlement orders that the "promising" subjects to be released and leaving the rest. Unfortunately, Tatsumaki was not deemed promising and as the monster smashes into her cell, she accepts her fate. However, Blast saves Tatsumaki by killing the monster and he immediately notices that Tatsumaki was merely hiding her true power. After convincing her to protect her own family, Blast gives her an advice: "When the time comes, don't go expecting someone to save you". Tatsumaki regains consciousness at the call of Fubuki, whom reassures her that help is coming. Tatsumaki decides to take Blast's advice and continue to take matters in her own hands, ready to fight once more.

With the barrier finally gone, Psykos makes a quick escape by flying into an underground train tunnel through the giant cracks that Tatsumaki created. Drive Knight continues chasing her with an onslaught of attacks. In an attempt to throw off her pursuer, Psykos shoots up at the tunnel ceiling and makes a giant boulder crash down. Drive Knight is unfazed as he detaches an energy blaster that vaporizes all the debris in the way. Psykos proceeds to eject several organic pods that shoot out reflectable lasers, filling the tunnel. While Drive Knight evades the lasers, he quickly notices the remnants of Orochi's cells within the tunnel while lamenting the fact that Tatsumaki was so powerful that she took them all out. A fully conscious Tatsumaki begins to crash large debris into the tunnel at Psykos' location in an attempt to stop her. Psykos transforms her jet into various forms that allows her to traverse through the terrain with Drive Knight following suit. As Psykos leaves the tunnel to the surface, Genos runs by and leaps on to Psykos' jet, throwing her off and allowing Drive Knight to catch up. Psykos releases more organic pods to take down Genos but Drive Knight uses his Bishop form, leaping onto her jet and shielding Genos from the attack. Drive Knight and Genos both open their chestplates and charge up their cores to perform a devastating attack, unleashing it into the jet, but Orochi counters by launching a massive beam from his own seared flesh that pushes Genos and Drive Knight off.

Freed again, Psykos makes one last attempt to shoot Tatsumaki, but the blast is intercepted by a boulder thrown by Tanktop Master. With the help of Fubuki's psychokinesis and ability to enhance his physicals, Tanktop Master unleashes a barrage of rubble toward Psykos, who dodges them. Both Drive Knight and Genos, who are reeling from the extended fight (the latter's upgrade about to overload and the former almost out of energy) agree to cooperate. Making a one-time gamble, the two combine their technology into a singular, powerful transformation: Promoted Rook, and intercept Psykos with a heavy strike, stopping the jet midair. Tanktop Master and Fubuki seize the opportunity to launch an entire building toward Psykos and Orochi, who tries to counter with an energy beam, only for the beam to be cut and deflected: Atomic Samurai, Puri-Puri Prisoner, and Superalloy Darkshine suddenly emerge from the flying building.

Genos taunts Psykos as Atomic Samurai uses his Beeline Atomic Slash, Puri-Puri Prisoner unleashes his Vibration Dark Angel Rush, and Darkshine follows up with his Superalloy Missile. Realizing that the fusion had taken too much damage, Psykos decides to split away from Orochi and escapes, just as Bang and Bomb rush forward and use their Cross Fang Dragon Slayer Fist to launch Orochi into the ground. Drive Knight takes the opportunity to collect the flesh sample he wanted, and Fubuki celebrates the S-Class' victory, only for Tatsumaki to interrupt her. Tatsumaki pulls the remains of the spire out of the ground and shapes them into a massive lance made of rock and green light, before pointing it down toward Orochi's remains and shredding the monster to pieces.

Trivia

 * This is the second major battle in which multiple S-Class heroes cooperate with each other to defeat a common enemy, the first being Atomic Samurai, Bang, Metal Bat, and Puri-Puri Prisoner vs. Melzargard.
 * Murata discussed several aspects of this battle in streams from 2018 (two years before it started), particularly Genos' dragon transformation. The ending of the fight bears a strong resemblance to a scrapped draft of a fight where the S-Class heroes took on Orochi; as in the original draft, eight S-Class individuals (Genos, Drive Knight, Tanktop Master, Atomic Samurai, Puri-Puri Prisoner, Superalloy Darkshine, Bang, and Bomb) help take down Orochi before he is ultimately finished off by Tatsumaki.