Knock Out is a medical officer and former member of the Decepticons. Originally, he was relocated to Earth after being summoned by Starscream to aid the damaged Megatron; Knock Out soon made a rival in the Autobot scout Bumblebee and when Breakdown was killed by Airachnid, Knock Out took a less active role for the Decepticons, in part due to his reliance on the former and resorted to using various weapons to get his point across during battles. Knock Out no longer served as an antagonist in the series after he joined the Autobots in Predacons Rising.
Once the Autobots defeated Megatron and took over the Nemesis, Knock Out claimed joining the group as they were restoring Cybertron. He was knocked out by Miko in the Apex Armor and taken as a prisoner to the planet. There, Knock Out helped the Autobots while they were under siege by whacking Starscream with the Immobilizer from behind, destroying the device in the process, and proving that he really wanted to join them. The team welcomed Knock Out into their side and he remained with them ever since.
First Appearance/Museum Heist
Knock Out was called on by Starscream to see if he can repair Megatron. Starscream chastised Knock Out for being late but he explained that it was "a long drive" to which Starscream reacted with distaste towards Knock Out's choice of altmode and wonders why any self-respecting Decepticon would choose a land altmode, when he could fly. Knock Out replied that he enjoys how he looks in his current appearance. Starscream then asked if he could repair Megatron. Knock Out said that he was better at "breaking them than fixing them" but agreed to do his best.
Later, Knock Out and Breakdown interfered with the Autobots' museum heist to take the Energon Harvester. He pulled up to Optimus Prime in vehicle mode and wolf whistles at Optimus' altmode. He and Breakdown then engaged the Autobots while Soundwave made off with the Energon Harvester taken from the human children. After Starscream began using the Harvester on Energon deposits, he and Breakdown disabled each other in an attempt to stop Bulkhead from interfering. When they come to the other, Autobots show up to help Bulkhead. Breakdown asked whether they should fight, but Knock Out decided to drive away instead.
Later, Knock Out participated in human street races, one such race resulting in him driving an opponent off the road for scratching his paintjob- when he returned to the Nemesis, Starscream confronted him about his street racing and ordered him to continue working on Megatron, and not to race again. Later, Knock Out does indeed race again, but this time, he happened upon Bumblebee, who is racing with Jack. He attacked them, but they managed to escape. When another kid, Vince, found Jack, Knock Out took him hostage and forced the Autobots to give chase. He and Breakdown set a trap to keep the other Autobots occupied, but Optimus Prime is able to save Vince by tearing off Knock Out's door, sending a furious Knock Out fleeing into the distance. When Knock Out returned to the Nemesis after the ordeal, Starscream punished him for disobeying orders, though the punishment was only cosmetic as Starscream scratched his paint job.
Deal with Starscream
When the all amazing Starscream decided he wanted to terminate Megatron by "mercifully" taking him off his life support, he made a deal with Knock Out where he would be the new Decepticon leader with Knock Out as his second-in-command. To this end, Knock Out did his best to convince Soundwave that Megatron would not have wanted to remain in a "vegetative" state and that taking him off life support was the only solution. However, they discovered Bumblebee and Arcee doing something to Megatron's body, and as they fled, they knocked Megatron's life support system off. However Soundwave pointed out they could not let Megatron die by an Autobot's hand, so Knock Out was forced to reconnect his life support. Later, he noted to Starscream that Megatron was no longer showing any brainwave activity.
He subsequently informed Starscream that he was not yet leader, but still open to the idea of being a second-in-command. When the Autobots interfered in Starscream's latest plan to recover the Energon, Knock Out assured Starscream that his second-in-command would take care of them, and ordered Breakdown to attack. However, Optimus Prime attacked from behind, and Starscream chastised Knock Out for not keeping an eye on the rear. Starscream's exact words were "What good is a second in command who fails to watch the rear!"
Aftermath of Megatron's recovery
Following Megatron's miraculous recovery, Knock Out was assigned to keep Starscream functional as Megatron punished him repeatedly for his duplicity- Starscream disobeyed his orders to simply recover, and later Knock Out saw to him as Starscream claimed he had lost his arm and it was Knock Out's fault for not checking him thoroughly. To make up for this, Knock Out suggested an upgraded limb, or else find his old arm. Starscream returned from searching even more damaged, and Knock Out pointed out that he needed to take better care of himself.
Knock Out and Breakdown were sent to steal a data cylinder which transferred all its data into Bulkhead by a laser due to Miko's clumsiness. After detecting Bulkhead in a monster truck platform, Megatron ordered Knock Out to bring Bulkhead's head. When Knock Out and Breakdown were searching through the platform for Bulkhead, who was in vehicle mode, the Autobot transformed when Knock Out was about to inspect him, then painted some of his mathematical (or possibly scientific) equations on Knock Out. This outraged him. Before he could use his buzz saw to cut out Bulkhead's head, Miko bumped herself into his head and the data came out of Bulkhead through a laser again. The data was lost in space, then Knock Out and Breakdown retreated
after Optimus, Arcee, and Bumblebee came.
At a certain point, Knock Out and Breakdown were stealing Energon cubes and Arcee was in pursuit of them until the air support Vehicons came and would have killed her if Ratchet had not intervened. Knock Out claims that he saw Ratchet for the first time saying he is a new Autobot. Megatron got assaulted slightly with energon leaking out of his mouth after Ratchet punched him in the face. Before Ratchet was able to punch him again, Megatron punched the green Energon liquid out of him. Knock Out collected the liquid back into a container, then battled Ratchet while trying to decapitate him. After Knock Out aimed his circular saw at Ratchet, but Ratchet dodged it, causing him to miss and pinned his saw to the rock-wall. When Ratchet picked up the container, Knock Out teased him in a rude tone, asking if he was going to drink it. Ratchet then remarked, "No...I'm going to destroy it!" he threw it against the rock-wall, shattering and destroying the container. Knock Out gasped and stated that Megatron would have his head for his failing to collect and present the new energon. Knock Out again retreated when Bumblebee, Arcee, & Optimus came.
He reported that the Space Bridge 2.0 was almost finished and joked on how he could hear Unicron's thoughts to Airachnid. He was present when they were rendezvousing with the portal, but his Lord left and left him wondering if he was losing it. Knock Out questioned Commander Airachnid when she suggested to abandon Megatron and witnessed Soundwave taking her down. The crew was surprised to see Optimus as Orion come with Megatron. Aboard the Nemesis, in the laboratory, he gave Orion the Decepticon Insignia.
Relic hunt/ Knocked out
Knock Out would become even more humiliated during the search for the Iacon Relics, as an infusion of Dark Energon caused the Nemesis to develop its own intelligence, thereby sending him and all the other Decepticons into stasis. This would be followed by a right cross to the jaw by the Autobot medic Ratchet. A chance to recover one of the relics in New York led to a fight with Arcee and Bumblebee, with the end result of Knock Out being run over by a sweeper train. A close inspection of Laserbeak would have Knock Out frantically trying to get rid of a live grenade. He would later be embedded inside a wall, courtesy of Smokescreen. His only real success was obtaining a Predacon bone, but not without a great deal of trouble. 
Dark Energon Experiment/ Terrorcon attack
With the return of Shockwave and his demotion to becoming his subordinate, Knock Out agrees to Starscream's plan to inject Dark Energon into the body of Silas,  only to have him to become an Energon-hungry zombie. This in turn causes the release of Airachnid and cutting the Vehicon forces in half as they were infected by Silas and became zombies as well. The end result was the banishment of Airachnid and the Insecticons to one of Cybertron's moons and a severe reduction of the remaining Decepticon forces on Earth. Airachnid was also a terrorcon, as seen in the last scene of the episode.
Due to his experiments with Synthetic Energon, and with the aid of Shockwave, and the captured medic Ratchet, Knock Out played a role in restoring the Omega Lock with the intent of restoring Cybertron and cyberforming Earth. However, he also played a vital role in the Decepticon's downfall by merely letting it slip in front of Ratchet that Megatron had set up the Autobots into finding Shockwave's lab and destroying the Predacon clones so the clones would not have a chance at destroying the Decepticons themselves, all of which Ratchet revealed to Predaking when he was at the Predacon's mercy, and then deactivated the Nemesis' shielding allowing his fellow Autobots to storm the warship while Predaking turned on Megatron. When the Autobots attacked the Nemesis, Knock Out decided that it was time to jump ship and tried to escape, but was prevented from doing so in the ensuing crossfire. In the end, he witnessed Cybertron being restored, calling it a 'lustrous sight.' When given odd looks by the Autobots seeing him, he responded with the statement of What, I'm joining the winning team. Knock Out was immediately knocked out by Miko, who was in the Apex Armor. Knock Out was then placed in a holding cell with the remaining Decepticon troops.
Predacons Rising Movie
Knock Out was held captive with the other Decepticon troops in a holding cell where they were all in stasis cuffs, which they used to hit against the walls and surroundings of the cell to get Bumblebee's attention. Bumblebee heard them and asked them of what they wanted. Knock Out and Bumblebee engaged in a short conversation. When Bumblebee brought up Knock Out's buffer regarding to his finish as "looking drab", Knock Out gave Bumblebee information on where to find Shockwave's lab. Eventually, Knock Out was freed by Starscream, which he told him that they could finally get off the ship. Starscream told them that they need to take over the ship.
Knock Out trapped Smokescreen in the wall the same way he did to him a long time ago and was present on the bridge. When Starscream announced his plans to use the warship as a way of fleeing Cybertron, Knock Out suggested they should try Earth, since Unicron was no longer present there. When Starscream yelled at Knock Out to shut up, Knock Out seemed hurt and could be seen thinking, probably about his place in the situation, as Starscream continued talking.
While Bumblebee fought Starscream over the Immobilizer, Knock Out used the Phase Shifter to take the Immobilizer from Starscream, and then whacked Starscream with it, which destroyed the relic. Bumblebee, however had said that it was not in fact the immoblizer. When Knock Out asked the Autobots if they now believe he wanted to join their cause, they have him a grumpy look in return as Bumblebee told Knock Out that they needed the relic, by using Ratchet's most common sentence: "Knock Out! We needed that!" He came back with "Wait... It really was the immoblizer?"
Regardless, Knock Out was welcomed and escorted Starscream to his cell with Arcee and Smokescreen. When Arcee asked why he turned against Starscream, he replied that even if he did help Starscream, Knock Out would've been the first to be fired out the airlock, which he also states "Oh, and he's rude" about Starscream. Knock Out and the Autobots faced against Unicron's army, with their three Predacon allies. The Nemesis crashed and the all survived, thankfully. After the Predacons were pushed with their undead ancestors in the well, Optimus and Wheeljack returned with the All Spark. After a short battle between Optimus and Unicron, Bumblebee, Smokescreen and Knock Out tried to aid Optimus. After that, Optimus trapped Unicron's spirit inside the All Spark's container. Megatron is back in his new body and Starscream tried to bring back the Decepticon ranks. Megatron said the Decepticons were over and flies off into the galaxy.
Knock Out was present with the rest of the Autobots with Optimus Prime. Optimus told them that they have acted like true Primes and Knock Out replied by saying that he looks up to Optimus as a best role model. After Optimus sacrificed himself, Knock Out was amazed along with the other Autobots, as the Well of Allsparks began shooting sparks out. Optimus's sacrifice restored their home world and as the team watched the sparks, a red spark, presumably Optimus's spark, shines out.
Knock Out is relatively short in height compared to Starscream (but extremely short compared to Megatron), he is more sized like an Autobot. He is bright red in color, with red accents; like most Decepticons, his optics are red. His finish is usually very shiny, though not quite as shiny as Smokescreen's and he seems to be a bit vain when it comes down to his appearance. In vehicle mode, he has the appearance of a bright red European sports car, called an Aston Martin, with the inner part of his wheels painted a shiny gold color.
Knock Out is, essentially, the Decepticon's version of Ratchet. However, rather than being grumpy, Knock Out is cheeky, arrogant and very vain. He values his own appearance above everything else, including the welfare of his patients. When he was about to abandon the Nemesis, his greatest concern was taking along his best rotary buffer. He is also shown to not like losing very much.
He is constantly arguing with Starscream, though at times, his personality often mirrors that of the backstabbing Decepticons and Knock Out won't hesitate to grovel or even change sides if the situation warrants it, stating that he is "joining the winning team." He is also a coward, though his cowardice is mainly due to his concern about protecting his finish or his own life. He gets very upset when his paint/finish is scratched or ruined and if someone defiles his paintwork, he will gladly do the same to the offender. Like most Decepticons, he considers the Insecticons to be an annoyance and find them disgusting. He has a definite cruel streak and will gladly perform experiments on living prisoners without any moral qualms as shown when he grins nastily as Cylas is relegated to his dissection table stating that he believed his former partner would be amused. He considers humans as nothing but bothersome, though he does admit that they do create some 'fine-looking automobiles', as well as enjoyable fiction, such as horror films revealed that he had watched at drive-in-theaters and has taken into some Earth customs as he wouldn't mind living there.
Interestingly, he does seem to have some sense of morals, like when he sided with the Autobots in order to save Cybertron from Unicron. He seems to genuinely like his partner Breakdown as he was deeply angered when Breakdown died. He also appears to have at least a small amount of humility due to his apparently humble reaction to when Optimus openly accepted him as an Autobot. He also appears to see Optimus as a role model, which shows he knows who to look up to. He also is fairly polite and seems to enjoy it when others are polite to him.
This indicates he is not truly evil, just a little unhinged, amoral, and self-centered. He may also be a narcissist.
Powers and Abilities
Knock Out is a competent scientist, doctor, and surgeon. He successfully performed a t-cog transplant on Starscream, and an arm replacement on Megatron. He carries at least one arm mounted drill and two built in hand buzzsaws. He also carries an energon prod around but it seems he cannot ever use it again after it was broken by Dark Energon and Synth-En infused Cylas in Thirst.
Knock Out is not a good fighter, mainly because he would avoid getting involved in fights and avoid messing up his paint job. He mainly uses powerful weapons to his advantage, which can also be used against him. Also his concern for his appearance is one of his flaws.
- "Sweet rims, 24 gauge? You're a real heavy duty... just like my friend here." - Knock Out to Optimus. (Deus Ex Machina)
- "I like the way I look in steel belted radials." -Knock Out to Starscream. ( Deus Ex Machina)
- "You scratch my paint, I scratch yours!" (Speed Metal)
- "I'm not only an automobile, I'm an automobile enthusiast."
- "No worries, Herr Commandant."
- "Buff this!"
- "Where is the Two-wheeler...?
- "Do you know how hard that is to replace?!"
- "No... Not the finish... Anything but the finish!"
- "Doctor in the house." (Sick Mind)
- "Same old..."
- "Long enough. And it's Commander Knock Out once and future, Lord Starscream." (Out of His Head)
- "Well... on the bright side, this provides an excellent opportunity for an upgrade." (Shadowzone)
- "Come to papa."(T.M.I.)
- "Breakdown forget the human. Games are only fun to play... when you're winning."
- "You painted my paint job! Prepare for surgery!"
- "You idiot! Megatron will have my head!" (Stronger, Faster)
- "Watch out for the quiet ones." (One Shall Rise, Part 3)
- "Catch me if you can!" (Operation: Bumblebee, Part 1)
- "Sporting of you."
- "You're not even gonna try and shoot up my tires? Bumblebee, where's your famous horse power, huh? Show me some speed!"
- "What is with the rental car?"
- "I'd stick around and do some donuts around you... but I have a delivery to make."
- "I live to serve, Lord Megatron. But..... What exactly is it?" - Knock Out wonders what relic he has found (Operation: Bumblebee, Part 2).
- "I think I leaked a little transmission fluid." - Knock Out gets scared.
- "It appears the ship now possesses a will of its own." (Flying Mind)
- "You have lovely features. Perfect for a painful little procedure I like to call the nip and tuck." (Tunnel Vision)
- "Shock and drop."
- "GRENADE! " *ducks and covers* (Triage)
- "I JUST BUFFED THAT!!!" (Hurt)
- "This is the human who dissected Breakdown." *extends his drill and buzzsaw with an angry scowl on his face* "Please, my liege, allow me to return the favor." (The Human Factor)
- "I will leave no fiber or fiber optic unexamined." *taps Cylas's face with a finger* (The Human Factor)
- "Breakdown would be tickled." - Knock Out says in a somewhat fond voice to Silas right before he subdues him with an Energon Shock Prod (The Human Factor).
- "Coming up." (Alpha/Omega
- "Soundwave's on fire. And so am I!" (Hard Knocks)
- "Wakie wakie..." (Inside Job)
- "Ha! Made you squirm. I do so resent a finish flashier than my own."
- "I beg you my Liege, release me from this absurd predicament!"
- "This is going to be juicy!" - Knock Out getting ready to watch a good show (Patch).
- "Uh oh. Does this thing have a fast forward button? Or, better yet, erase?" - Knock Out's past comes back to haunt him. (Patch)
- "Awkward..." (Patch)
- "We? Unless nagging counts, I haven't seen you lift a finger!" (Regeneration).
- "Well... Perhaps if my research wouldn't been sidelined by someone's cosmetic surgery, I'd might be further along right now!"
- "Oh Gee, why didn't I think of that?"
- "Careful Starscream, you may dislocate a landing gear putting yourself on the back." (Scattered)
- "Hmm could happen." (Thirst)
- "Its alive!" Knock Out imitating Dr. Frankenstein. (Thirst)
- "Not really. Besides, Cylas once had poor Breakdown pinned to his lab table. I think my former partner would be pleased to be a part." (Thirst)
- "Gone..... Completely drained of Energon. Tell me something, Starcream when you said "problem solved," is this even close to what you had in mind?!" (Thirst)
- "And you're the monkey wrench who thought it was a good idea to dabble in voodoo!" (Thirst)
- "... You're welcome."(Synthesis)
- "Guards!!!! Help me extinguish this inferno before it scorches the project, and my finish!!!"
- "Pack light... Pack light... (finds his favorite buffer)... Ooh! Pack smart!" (Deadlock)
- "Ah, such luster" *everyone stares* "What? I'm joining the winning team."
- "Now do you believe I'm joining the winning team?" - After Knock Out betrays Starscream and joins the Autobots (Predacons Rising).
- "Even if I had helped him seize this ship, he would probably just fire me out of the first airlock... Oh, and he's rude." - Knock Out does not like Starscream anymore.
- "Zombiecon! Zombiecon!"
- "Well, I've... never had the best role-models." - Knock Out is inspired by Optimus Prime.
- Although other Decepticons in the series have shown signs of losing faith in the Decepticon cause, Knock Out is the first to actually change sides, even with Dreadwing, who gave the Forge of Solus Prime to the Autobots.
- Though the premise of Predacons Rising states that the Autobots, Decepticons, and Predacons unite as one, Knock Out is the only Decepticon who actually joins the Autobots and Predacons as Starscream was a prisoner on the ship and Shockwave disappeared.
- Knock Out's rivals in the series appeared to be Bumblebee and Ratchet. That all changed in the Predacons Rising film.
- Knock Out never refers Optimus by his name. Referring to him as Big Rig, The best of role models, or Big O.
- Knock Out likes to buff his finish often.
- Knock Out faced off against Bumblebee and Arcee in the two separate relic hunts.
- Knock Out appears to enjoy competing with Bumblebee in racing.
- Though his partner near the beginning of the show was Breakdown, Knock Out ultimately got in the most mischief with Starscream. Such as planning to assassinate Megatron and (unintentionally) unleashing a horde of Terrorcons aboard the Nemesis.
- It is noted that Knock Out is a part-time medical assistant to Ratchet, and a Soldier in the field.
- Like Dreadwing, Knock Out was more of an anti-hero than evil, before changing sides. Though while Dreadwing was honorable, Knock Out did appear to enjoy tormenting others.
- In Thirst, Knock Out used the same line as Arcee in Scrapheap, when he was about to get his energon drained by Terrorcons, along with Starscream: "I find it rather ironic that after battling Autobots all these years, getting smacked down, shot at, blown up, this is how our lights go out?" (bold= same line as Arcee).
- Knock Out sometimes uses foreign words of European language, such as German and French. This suits him well, do to his chosen vehicle mode being a European sports car.
- Knock Out and Megatron are the only Decepticons of rank who eventually disband from the Decepticons of their own free will. Though Starscream did so as well, Starscream rejoined the congregation during the second season and stayed a Decepticon till the end.
- Although he was the most concerned about Predaking turning on them in Evolution, he is ironically the very person who allowed that to happen by slipping up in front of their prisoner.
- Although there is speculation over whether Knock Out may be attracted to other Cybertronians, word is that he is first and foremost in love with himself.
- In Transformers: Robots in Disguise season 2 episode 9 called Impounded, Strongarm was next to a vehicle mode that appears quite similar to Knock Out's car mode. Given her statement of being stuck with "common criminals", she made a comparison to Knock Out's old personality.
- Knock Out's vehicle mode appears again in Transformers: Robots in Disguise season 3 episode 10, "Disordered Personalities" as a racer in the Crown City Grand Prix. Knowing his love for street racing in the past, it's a nice reference to Transformers: Prime.
- Knock Out says that Starscream is rude.
- Knock Out's vehicle form resembles that of the Aston Martin One-77.