Spoilers are ahead. Read the story here.

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It all started with an experiment. Doctor Scarlett Fox was doing some experimental research into time and space. This caused Rex Dangervest, a threat from prior to the Unikingdom's founding, to rematerialize. The Unigang doesn't trust him for the most part, for very obvious reasons, so they throw him in an improvised dungeon in Dr Fox's lab. There would be no real way of escape for him anyway if he broke out of the dungeon because his ship is no longer in the timeline.

He starts to form a bond with Puppycorn, who reminds him a bit of Emmet, and Unikitty makes it her goal to help him be less gloomy. His true nature as Emmet's future self is eventually revealed to her, and Unikitty updates her goal to make him more like Emmet. Rex, who is still learning who he is and who he wants to be now that he's no longer out of the timeline, really doesn't want this. In her desperation, she uses one of Dr Fox's experimental devices, the happy horn. This changes his brain waves to be more like hers, but it only lasts so long. By this point, the unigang trusts him enough to have his own room in the castle. However, with his trust broken, he leaves the castle to find another place to live and explore the kingdom. He eventually settles on the Action Forest and invites Unikitty to come find him when she's no longer stuck in the past.

Meanwhile, the timeline begins to loop. It's eventually revealed that the timeline loop is at its most intense on the planet Undar, with time looping to the point where Rex crash landed there. By the time this is known, time is looping all over the galaxy. Rex realizes the timeline is looping because of him and his actions and ends up building a time machine with Dr Fox's help, Unikitty going between the two of them to deliver and gain supplies and information. After the time machine is built, Rex leaves to solidify the timeline as something a little bit more than Emmet's future self, since his exposure to the magic of the Unikingdom changed him enough to stabilize him on the timeline. He promises he'll see the others again someday.

The timeline is repaired, but changed.

Thanks to another device of Dr Fox's design, a device that makes things more exciting, Rex ends up crash landing on their front lawn. Like in the previous timeline, the unigang doesn't trust him. Unlike the previous timeline, they decide to keep him far away from the castle and allow him to live in the Action Forest. Unikitty tries to learn more about him, but Rex's apprehensive. He refuses to trust her until he has no choice but to reveal that he's Emmet from another timeline. After his true nature is revealed, the Doom Lords start to come out of the woodwork to ask him to join them as a contractor. He refuses multiple times, saying he doesn't want to be the bad guy anymore.

The Unikingdom's first anniversary approaches and Queen Watevra Wa'nabi gifts the kingdom with the Gems of Ackrilique, powerful gemstones from another world that enhance the innate ability of their holder. Around this time, Rex changes his name to RJ Brickowski, because he no longer feels like he's Rex Dangervest or Emmet.

The Doom Lords make a play to steal the gems and succeed, leaving the Unigang with only one. They run the group out of the castle and start to wreak havoc on the kingdom using the gems. The gang attempt to steal the gems back with the help of Captain, a Puppycorn from a future where the Doom Lords succeed and RJ died in the attempt to stop them.

They eventually get back every gem but one and it is revealed that the Doom Lords' ultimate goal is to level the planet and blame everything on RJ. By working together, they manage to stop this plan and save RJ from losing his life.

Peace eventually settles in the kingdom until Unikitty starts having bad dreams about an Armommageddeon like event. She sees this as visions of the future, but she notices the things don't add up around her as well. She tries to reach out to Richard for guidance, but he's nowhere to be found. The dreams intensify as well as her friends' odd behavior.

Eventually, RJ disappears as well and she has visions of both his and Richard's deaths. She gets assistance from the Score Creeper in the form of a jar that contains what Dr Fox reveals to be a memory from the Memory Machine, a device in her lab she does not remember building. She has been looking into something in her files known as Project Lotus.

As it turns out, Richard is the reason for RJ's disappearance. He's been watching everything play out and kidnapped RJ in the middle of the night to keep him from exposing Unikitty to Project Lotus. He begs him to start Armommageddeon to "fulfill" Unikitty's prophecy. RJ refuses to do that and instead attempts to appeal to Richard's true nature, seeing that he's acting out of desperation. Richard is reluctant, but eventually is talked down enough to agree to let RJ in on what Project Lotus is about.

It's revealed that Project Lotus is a promise to keep the true nature of the Unikingdom under wraps. This kingdom isn't the first version of the Unikingdom that Unikitty has ruled over and not the first time Unikitty has known and befriended the rest of the unigang. The original kingdom was destroyed in an apocalyptic event, one that none of them could fight and ended up sending everyone but Unikitty into the Bin of Storaj. What Unikitty thought were visions of the future was actually her suppressed memories of the past resurfacing due to the stress of the Doom Lords invading and RJ starting a similar apocalyptic event a year prior. Now that Unikitty knows the truth, she is reassured by the fact that RJ is now a true friend and willing to help her through her trauma.

During a road trip, RJ and Richard grew closer. They started dating, trying to keep the relationship secret. Of course, it's not too hard for their friends to tell what was going on. They get married years later while the kingdom moves into a Crystal Age thanks to special crystals that catch the magic of the world around them which can be converted into a clean energy.

The world is at peace...