Mighty Big Trouble is the fourth episode of Season 2 1/2 and the forty-third overall of Transformers: Robots in Disguise.
Sideswipe puts his foot in his mouth and Clawtrap digs up something Starscream is more than happy to relieve him of.
The team return from a mission in Egypt with a new relic. Fixit identifies it as a high energy pulse generator, which could produce short, intense energy bursts that could shut down or destroy a bot's neural net. Unfortunately, Jetstorm and Slipstream trip up on the sand and accidentally activate it. When the Mini-Cons trip themselves up, Sideswipe slashes the generator apart with his Decepticon Hunter before it could fry their brains. Sideswipe then makes a few jokes at the Mini-Cons' expense, something no one finds funny, particularly the Mini-Cons.
At an uncrewed, automated cargo ship, the Scavengers arrive in their ship. They're tracking something that's giving off more power than they've ever found before. Clawtrap, Thermidor, and Scatterspike grab three Mini-Cons for a power boost before they start searching the ocean, leaving Paralon with the rest. The trio soon come across a sinister-looking sword buried in the ocean floor.
Bumblebee asks Fixit if there's any sign of Optimus, but there's still nothing. Sideswipe tries to join in with humor, but he's met with cold reception from the others and silence from Fixit. Sideswipe makes a half-hearted apology to Fixit but he only leaves. Bumblebee and Strongarm tell him he needs a proper, sincere apology.
The Scavengers emerge from the ocean with their prize. However, as soon as their back is turned, the Mini-Cons steal the ship and fly off. Moments later, a portal opens and Starscream emerges from it and demands to know where his Mini-Cons are. Clawtrap is shocked that the Mini-Cons have been running from Starscream and tries to cut a deal as the rest of Starscream's crew comes out of the portal. Then Starscream sees the sword and identifies it as the Dark Star Saber. Starscream takes the sword and boasts with it and the Mini-Cons, he'll able to not only take revenge on his old master, but conquer galaxies. He demonstrates its power by sending Paralon, Scatterspike, and Thermidor into the ocean with an energy wave, though the Saber starts resisting afterwards. Starscream threatens Clawtrap to tell him where the Mini-Cons are and send him into the sea when he tells them the Mini-Cons have fled. Shadelock points out that Starscream doesn't need the Mini-Cons with the Dark Star Saber, but Starscream disagrees. He tells RoughEdge to bring his ship down from orbit and start scanning for the Mini-Cons' energy signatures.
Sideswipe tries to think of a way to properly apologize to the Mini-Cons, Russell suggests he use flowers and a poem. Bumblebee and Strongarm discuss how the new Mini-Cons seemed reluctant to aid their Decepticon partners as well as how powerful they are. Fixit notes that there is a strong symbiosis between Weaponizer and Bot; the host gets powered up, though it's unknown to what extent. And yet Bumblebee felt that the Weaponizer was holding back for some reason. Unknown to them, Aerobolt infiltrates the scrapyard and disables the defenses, allowing the other Weaponizers to get in to get the Cybertronian tech they detected to modify their ship.
Jetstorm and Slipstream spar and complain about Sideswipe's behavior when they hear a noise. Spotting Sawtooth and thinking they can handle one Mini-Con, the duo attack him only to soon find themselves surrounded by the Weaponizers. Sideswipe tries to deliver an apologetic poem to Fixit, but it's less than impressive. The team soon hears the fight and rush to investigate. The Autobots arrive just after Jetstorm and Slipstream are disarmed and knocked down. Despite trying to keep the Weaponizers out of their hands, the Mini-Cons seize control of the Autobots one by one. Fixit comes across the controlled Autobots and claims he'll be on vacation on Alpha Centauri before trying to run. Sawtooth stops Tricerashot from pursuing Fixit and reminds him they're only here for the H.E.P. generator. When Fixit tells them it was destroyed, the Weaponizers abandon their hosts and leave. The Autobots give chase while Drift leaves his students behind in case they return.
However, as soon as the Autobots leave, a GroundBridge portal opens and Starscream's crew emerge. Shadelock mistakes the Autobots' Mini-Cons for the Weaponizers and captures them. Bringing them back to Starscream, the Decepticon commander is annoyed that they've brought him the wrong Mini-Cons. Fixit tries to clear up the confusion, but soon lets slip that Bumblebee is his commanding officer. Starscream is delighted by this news.
The Autobots return to the scrapyard to check on the Mini-Cons, only for Denny and Russell to tell them that Decepticons have captured them. Starscream soon sends a holographic message to Bumblebee, saying he's willing to return their Mini-Cons if Bumblebee surrenders. Bumblebee drops his Decepticon hunter and Starscream opens a GroundBridge for him to step through. Bumblebee promises his team this isn't over before going through. Sideswipe and Drift are worried about Bumblebee and the Mini-Cons, but Strongarm points out that Starscream is out of their league. Fortunately, a Cybertronian ship arrives; Optimus Prime has returned.
"Oh please; there will be plenty of time for bowing and scraping. Now, where are my Mini-Cons?"
- —Starscream's back.
"There's no such thing as too much power. Not as long as there's more to be had."
- —Starscream lets the power he has go straight to his head.
"Autobots are good,
Decepticons are bad.
I'm so very sorry
That I made you...angry."
(The others stare at him)
"I couldn't think of anything that rhymes with 'bad'. What?"
- —Sideswipe's no poet.
"How...how can you control me when..."
"When I couldn't control you? Maybe it's because we're both dinos, I don't know!"
- —Grimlock and Tricerashot try to explain last episode's inconsistency.
"Hello, Bumblebee. Nice to see me, isn't it?"
- —Starscream metaphorically strokes his goatee.
- The Dark Star Saber was last seen in "Deadlock", falling off the Nemesis to plummet to Earth.
- Tricerashot attempted to take over Grimlock in the previous episode, but reveals it probably didn't work because they were both Dinobots as he hypothesized.
- Fixit notes that Starscream's chassis does not match his records, the only instance of visual differences between series being called out among the "Aligned" shows.
- Starscream's motive of getting revenge on Megatron seemed questionable considering his loyalty to him near the end of Transformers: Prime, as well as the thrill of Megatron essentially "surrendering" the throne to him in "Predacons Rising". However, he would later clarify in the next episode that he wanted revenge for all of Megatron's cruel actions towards him.
- The high energy pulse generator resembles the relic containers seen in Transformers: Prime Season 2.
- Alpha Centauri is a star that has been featured in Transformers fiction before, sometimes as Cybertron's sun.
- The "automated vessel" the Scavengers land on appears to re-use the animation model of the oil tanker Windward from "Trust Exercises".