Here is how Bumblebee interrogates Barricade and how Optimus Prime kills Barricade in Transformers: Robots Among Us.
"I can say without a doubt that there are an infinite number of universe. Some much like our own... But for one or two occasions, exactly the same." -Lex Luthor.
(The scene opens in the Transformers: Robots Among Us Universe where we see one of the white statues from the first movie at the rubble, but as it zooms out, we see that all of Mission City is in ruins with the headline "MISSION CITY DESTROYED - MILLIONS DEAD". This screen was shown inside the Chicago N.E.S.T HQ where everybody in the building is in shock, panic, or in disarray in slow motion. We then hear evil laughter coming from behind a door)
Barricade:(gets slammed onto the chair)
Bumblebee:(slams his fist on the table) The nuke, where'd you get it?!
Barricade: Why, you want one?(jeers) Copy bot.
(Suddenly, the wall bursts open as Optimus Prime walk in, rage in his eyes)
Optimus Prime:(with rage in his eyes) Get away from him, Bumblebee!
Bumblebee: I'm handling this, Optimus.
(Optimus walks over to the table, tosses it aside then picks up Barricade and slams him against the wall)
Optimus Prime: You drugged me! Me - Vixen Sigma... My son...
Barricade: First Cybertron, now Mission City. The people you love really tend to die around you, don't they?
Optimus Prime:(raises his fist)
Bumblebee: Optimus, don't!
Optimus Prime:(punches the wall instead)
Barricade: Heh. That's why I like you, Prime. You're much more guillible than Bee is.
Optimus Prime:(throws him to the other side of the room)
Barricade:(gets up; pops his back; walks over to a chair) You think you can have a family? That locking me up will somehow magically make me an Autobot? And they'll be safe?(sits down) So big. So dumb.
Optimus Prime:(walks towards him)
Barricade: Now run along, so I can bust out of here. I've got lots of strategizing to do to top this.
(this reaches Optimus' breaking point as he lifts Barricade up by his neck from his chair)
Bumblebee: That's enough!
(But Optimus just pushes him aside as Barricade realizes whst's coming)
Barricade: I know it's soon, Prime, but... Think you will ever love again? Maybe you won't kill your next family.
(Optimus had had enough and transformed his hand into a sword and thrust it into Barricade's chest, killing him while Barricade grunted as he breathed his last breath)
(this was the only the beginning. Not only was his rival gone, but so was his leader)
(Over time, Optimus slowly became a killer. When his mentors Alpha Trion and Zeta Prime were kidnapped by Makeshift, Optimus recruited Chromia, Sideswipe, Ironhide, Elita-1, Breakaway, Windblade, and Arcee to his cause. Optimus, Arcee, Chromia, and Ironhide went to Alchamor Asylum to remove the inmates)
(We see Bumblebee and Prowl using their jet packs to fly to the prison)
Prowl: I don't get it. So what if Optimus' removing the inmates from Alchamor? They're the worst of the worst.
Bumblebee: He's going to kill them, Prowl!
Prowl: Hmph, sounds like he'd be doing us and the universe a favor.
Bumblebee: Killing sentient beings isn't justice! Optimus can't see that! He's letting his own negative emotions cloud his judgement.
Prowl: Yeah, and what if it had been Chicago?! If Barricade killed me, your own partner?!
(Bumblebee stays silent)
Prowl: Thought you'd say that.
(As they approach Alchamor Prison, the jetpacks suddenly begin operating on their own)
Prowl:(presses a few buttons on his jetpack) They're not responding. We're being taken back to the San Diego Base.
Bumblebee: Prepare to detach!
(He and Prowl press a red button that detaches them from the jetpacks back to San Diego Base, and open their parachutes, gliding towards the Alchamor. But then Bee looks down and sees a groundbridge open up. Out of it comes Ironhide, a member of the Regime. He fires his cannons at the two,
(Bumblebee and Drift went to stop them, only to be betrayed by Prowl, who killed Drift in the conflict. Bumblebee then recruited Amazonia, Strongarm, Jetscream, Hot Rod, Predaking, Lady Bee, Hound, and Grimlock to his cause. Secretly, he also recruited Major Malfuntion to his cause. Together, Bumblebee, Hound, Predaking, Strongarm, and Amazonia kidnapped Windblade, while Bumblebee secretly had Malfunction infiltrate the One Transformer Regime. When it was discovered that Windblade was still missing and Malfunction had replaced her by the Regime, Optimus and Arcee killed Malfunction. Later, Bumblebee, Amazonia, Jetscream, Hot Rod, and Predaking traveled to Team Prime Base to retrieve a prototype Energon pill that would enhance a Cybertronian's strength by ten thousand fold. However, the US President's distraction failed, Predaking and Optimus got into a fight. However, Arcee intervened, and shot his fire chamber, causing it to inflame all of his systems, including his flight systems. In a last ditch attempt to kill Optimus, Predaking flew high into the air, folded his wings, falling through the air, crashing into the ground, and exploding. Predaking died from the explosion, Arcee was injured, but Optimus survived. After Chromia took Arcee to safety, Optimus returned to Team Prime Base, where he murder Hot Rod. Meanwhile, Bumblebee returned to the NEST San Diego Base to analyze the Energon pill)