More summaries from the Wiki.
LG55 Slugslinger:
Shaoshao Li is surprised to be met with Spike Witwicky in the Legends World, and more so when the chairman (after telling her to dismiss any silly rumors about him being an impostor) informs her that all Transformers in this dimension will cease functioning the next day. Indeed, that day Slugslinger reveals that he has reacquired Caliburst, whose mutant ability to fire anti-electrons renders all other Transformers unconscious and frothing at the mouth. Even his fellow Targetmasters Triggerhappy and Misfire aren't spared, as Slugslinger takes the opportunity to steal Blowpipe and Aimless from them, showing no remorse for his betrayal and instead bragging that shooting people in the back is what he loves the most. Merging with a transtector rewarded to him by "Spike" for his services, Slugslinger then combines the three Targetmaster partners into a massive plasma energy gun so infused with the deadly energy that he dubs it the "Plasma Energy Chamber".
As the plasma energy emissions begin slowly disintegrating the unconscious Transformers, Shaoshao demands to know why Spike is working with a Decepticon, and he claims the Transformers must be destroyed as they're an obstacle that prevents galactic peace from ever being achieved. He notes that that Shaoshao should understand, having once hated them too, but she's moved on since then and doesn't hesitate for a second to transform into her Targetmaster suit and save Hot Rod. She is joined by fellow Targetmasters Sue, who fights for Kup, and White Lune, who now works with Blurr and fights for him too. Together, the three of them all take on Slugslinger, but he destroys their suits with a plasma energy burst. However, the energy doesn't affect the organics within, who slip past his defenses and successfully separate his head from his body and break apart the Plasma Energy Chamber. The Decepticon himself is knocked out by Caliburst's anti-electrons in the confusion, allowing Shaoshao and Hot Rod to capture and imprison him. Afterwards, Hot Rod wonders if Shaoshao is alright with defying Spike and being branded a traitor by the Galactic Peace Alliance, only for her to tell him to take the blame.
LG56 Perceptor:
Having heard that the Legends World was created by the Zamojin, Perceptor travels to the dimension in search of his old friend, Katsu Don, whom he's lost touch with and worries about. Highbrow looks forward to investigating the dimension's mysteries together with his fellow scientist, though Perceptor's first duty is to fix up Ramhorn, injured in battle to the point where his cassette mode is beyond repair. Perceptor replaces it with a new tank mode, and while Ramhorn hates it, the scientist insists that he made the right choice giving him a more mobile altmode is better. The group is then interrupted by none other than Katsu Don, who says he's here to "take back Nijika" before tearing Perceptor's head off and running off with it. Highbrow and Perceptor's colleague Minerva are ready to make chase, but Ramhorn warns them that the Zamojin are strong and that they should bring some extra firepower in the form of Perceptor's body.
Katsu Don brings Perceptor to the headless new body of Nijika, damaged in a previous battle, and, having recalled that Perceptor's parts are compatible with hers, attaches the panicking scientist's head to it. The process is interrupted by the other Autobots, who have reconfigured Perceptor's body into its rarely seen tank mode, and a combined barrage from both it and Ramhorn distracts Katsu Don long enough for Perceptor to remove his head from Nijika. He returns it to his original body and takes aim at Katsu Don using Ramhorn's third mode, a handheld weapon, and the Zamojin retreats, swearing he will fulfill his dream of creating a full-scale Nijika someday. Admitting that he wasn't actually going to open fire on his old friend, Perceptor hopes that Katsu Don will someday, on a night of falling stars, find the right path again.
After returning to Axalon, Perceptor figures that since his head was already separated, he might as well convert it into a small robot and live a comfortable, human-sized life. Unfortunately, this makes it less comfortable for him to use his microscope mode, as he now has to stand on Minerva's head just to look into the lens.