For the sake of not having to make my own digimon designs, I'm using pre-existing ones for this. The seasons of Digimon inspiring this one are Tamers, Frontiers, and Beatbreak.
Piemon/Infermon/Tsumemon (Caine)
He is not the villain, but rather was a useful idiot to what became the villains of this AU.
Caine as Piemon was capable of making more digimon and creating/closing rifts between the digital world and the real world. The way he makes digimon is via infecting devices with emotional energy that he can produce, but humans produce exponentially more of it. So when tasked by C&A to create digimon workers/soldiers he decided to link the humans in charge of him to the digimon being created. It worked, kind of...
The process turned the humans into digimon without a clear means to turn back and the more powerful they became, the more their human minds became unstable.
Now that most of the people Caine was working with have turned into corrupted mega level digimon, he's managed to escape with the help of the only one to help him create a means to avoid the corruption.
In their escape, he got separated from Tigervespamon and was beaten to the point he's fairly weak.
As Infermon, he used as much power as he could muster to find suitable humans to stop the evil digimon he's created. Now weak and vulnerable as Tsumemon, he is basically the annoying marketable plushie mascot character that the newly turned digimon have to protect if they ever want to find a way to become humans again.
Tigervespamon/Forgebeemon (Kinger)
The only one of the original team to not only consider their corporate leaders evil and to figure out the means to maintain sanity, he escaped with Caine and his wife, Queenbeemon. As he was separated from the one who can give his wife the patch that allows them to revert down evolution stages, he's left doing an alternative method for her.
That being collecting emotional energy for her to consume. He gathers this from the digimon acting as his former coworkers minions. It isn't much, but it keeps her calm in their shared hideout.
Sunflowmon (Ragatha)
The first human to fall victim to Caine's recruitment efforts. Like in the canon circus, our humans forget their name upon converting into digital form. Before Caine can properly onboard her to the mission to save the world, she is attacked by C&A minions and saved by Kinger.
When he recognizes her as another human, one with the form reversion patch, he flees with the data he collected before he's tempted to hurt her for the patch for his wife.
She ends up actively seeking him out, even after teaming up with other digi-destined as Caine calls the group.
Elizamon (Gangle)
The unwilling companion to Jax who despite how he talks down to her for her wanting to try to find normal people to help them, feels like she owes him as he does the fighting she'd rather avoid.
She is the only one to lose a fight hard enough to go into her Rookie stage. As she doesn't do much to change that, she stays in that stage, even when having downtime in the digi-destined's hideout.
Lekismon (Jax)
The only digi-destined who is all for beating up evil monsters and lacks care for any property damage along the way. He's the first to evolve to mega from the group and promptly has a mental breakdown.
If you know the main evolution line of the digimon chosen, you will know what triggers that breakdown.
TeslaJellymon (Pomni)
The last to be recruited and the first that Caine finds. She works with him to find the others and defeat The Board Members (the evil humans turned digimon who took over C&A).
Zed (Zooble)
The only human to remain human of the bunch. They own a building that has not only a bar, but a storage and event space that they use as a base of operations for the digi-destined after Jax and Gangle save them from one of The Board Members, ChaosDukemon.
They do not trust Caine and are wary of Kinger when he's brought aboard. Even so, they tend to hang back at their base where Caine is a constant nuisance to them with his curious, yet mischievous nature.
I started writing a fix-it fic and it escalated into a full blown AU.
The AU is currently called "I can fix him." and involves my OC forcing Caine to not die and then rehabilitating him along with facilitating updates to the circus. A whole lotta rambling about it below.
Some of those updates includes cast members being able to tweak their avatars and create conjure presets. Since humans have trouble conjuring compared to an AI, having essentially a set of accessible commands for things of use puts them on more equal footing to Caine.
They all keep things fairly the same because as much as you can make yourself pretty close to human, for some, it feels wrong to look in a mirror and see a human face after being in the circus so long. Kinger's big change being opting for proper legs took some adjustment, but Caine is also trying to just walk around more so they bond over the awkward shift in mobility.
Kinger's conjure presets are the most OP as Caine slipped him extra points under the table for them. The conjure presets are limited as the digital landscape can only handle so many extra processes running.
The one in the art above is called "Subjects". They are programmable units that can do various tasks depending on their type. Pawns are the most versatile, but can only complete their programmed tasks for a day before despawning. He can spawn eight at a time. Rooks can store data in themselves. Knights can connect other Subjects to each other. Bishops can create an external output. Those three can have two spawned at a time.
His other conjure presets are "Costume Change" which lets him swap his new casual outfit for the more royal robes and "Fortress" which lets him summon a small structure to hide in.
One of the general updates is a day and night cycle which helps Kinger go around the circus without needing a bucket over his head for mental clarity.
The cast can also customize their rooms so he's made his room a cozy dimly lit library where he has more board games than books.
Here's a piece of an Undertale OC of mine. He's a Wolpertinger (a jackalope, but with more animals thrown in the mix). His antlers come in seasonally, though. I didn't just forget to draw the antlers. No, of course not.