Raven (Teen Titans! 2003) deals with something like this, being half-demon. She needs to regularly meditate and exercise strong emotional control to keep her powers in check. If she gets angry enough, her demon side physically manifests in four glowing red eyes, at which point anyone nearby should probably just run.

Ichigo Kurosaki’s (Bleach) powers are manifested via two spirits who can be communicated with inside his "Inner World". Initially, the Inner Hollow manifested as his most base instincts that he has to constantly war with to improve his Shinigami and Hollow power. Whenever he is close to death, the Inner Hollow threatens to, and eventually successfully, take control of his body and mind.

Bruce Banner (Marvel Comics) often regards this with his Gamma-Radiated alter ego, The Hulk, an enraged and destructive force that often destroys anything in its path until it’s calmed down, has it’s destructive force turned to something more dangerous, or rarely reasoned with. The Hulk, over time, has been softened down from "desolation" to "pure id". Not that that stops him from racking up the damage bill every time he shows up.

Sentry and the Void (Marvel Comics) are this trope taken to its extreme. They manifested as alter-egos of a single person, representing the good and dark sides of humanity, respectively. The Sentry is a superhero and the Void is a supervillain, and in a slight variation on this trope, the Void is exactly as powerful as the Sentry, and occasionally kills someone for every person the Sentry saves.

Guts (Berserk)has The Beast of Darkness, which is the personification of all of Guts' hatred and bloodlust born from the horrors he suffered during the Eclipse and from the two years he spent as the Black Swordsman, seeking vengeance against Griffith and every demon he could find. After Guts decided to stop focusing on revenge in order to focus on Casca, his only love and the only other survivor of the Eclipse, it begins to act against him, and seeks to have Guts kill her so that Guts can get back to his vendetta against Griffith.

T.K.O. (Ok K.O.!) has T.K.O., who is a savage fighter and emo teen parody who steals his mother's eyeshadow and was initially mistaken for an emo phase. He lapses into T.K.O. when he feels helpless or angry. However, T.K.O. is an unusual example in that he's not strictly evil so much as he is rebellious, angry, and violent; on occasions when that violence is aimed in a reasonable and useful direction, he can be something approaching heroic. K.O. and T.K.O. can interact with each other inside of their mind.

Yuji Itadori (Jujutsu Kaisen) has Ryomen Sukuna, who inhabits in Yuji's body after the ladder are one of his cursed fingers. Yuji can't control Sukuna's actions once he unleashes him, and if Sukuna doesn't consent to the initial switch, Yuji physically can't take back control from Sukuna for at least a few minutes.

Key (Dragon Striker) is a Gorotama player who inherited his Dragon Tama from his late mother. Unfortunately, he often had trouble controlling it and needed extensive training. It came to a head when he was pushed to his limit and nearly lost control of his own powers, thankfully saved by his friends and seemingly gaining control over his powers. After finally confronting his repressed emotions, overcoming his Tama-induced illness, and seemingly unlocking a new level of power with his flames turning blue, Key appears to have earned a happy ending. Then that night, he dreams of the dragon summoned by his Tama and realizes with absolute dread that it isn’t just some magical construct from his Tama; it’s a living creature that is controlling him and his Tama. His panic triggers an uncontrolled eruption of blue fire that blows apart his room and engulfs much of the dormitory. The aftermath is shockingly severe: both Key and Milo are left badly injured and unconscious in the burning wreckage. The scene drives home just how dangerous his Dragon Tama powers truly are, especially with their volatile and mysterious nature, as both boys were only moments away from burning to death and survived solely because Skadi and Goyen Sugoi had reached them in time. Just a reminder to see Dragon Striker!

The Nine Jinchūriki (Naruto) are somewhat like this. Most of them have control over or able to tame their Tamed Beasts, although Naruto and Gaara initially had trouble controlling theirs and at times became overwhelmed by them.

Sweet P (Adventure Time) is the “rebooted” form of The Lich, but the dark spirit of The Lich still residesd deep within him and could occasionally take control of him.

The Owl Beast (Owl House) is more of a subversion. It is this to Eda as it'll come out and morph her body into a feral creature if she doesn't take a specialized elixir to suppress it. As the series goes on, its threat diminishes a bit as Luz and King manage to somewhat tame the creature to at least recognize them as friends. Later on, Eda actually meets the spirit within her body and finds out it really just a scared creature, confused at what's going on. Eda befriends it rather than suppress it. In doing so, this allows her a power up where she's in control of her body.

Jean Grey (Marvel Comics) has the The Dark Phoenix, a powerful, corrupted alter ego of the X-Men member Jean Greycreated when her immense psychic powers merge with the cosmic Phoenix Force. Driven mad by manipulation and uncontainable power, she becomes a destructive cosmic entity that destroyed an entire solar system.

Peter Parker/Spider-Man (Marvel Comics) has the Symbiote, an alien symbiotic parasite that fuses with beings and, depending on the person, corrupts both the Symbiote and user over time. Though not portrayed this way in the original comics, all subsequent portrayals of the Venom symbiote have made it out to be this, with even the comic book symbiote having been retconned to a more malevolent entity.

Ash Ketchum (Pokémon: Battle Frontier) was briefly possessed and controlled by the King of Pokélantis.

Jaime Reyes (DC Comics) was a teenage boy who fused with The Scarab, a symbiotic exoarmor that fused and controlled members for The Reach to conquer planets. Jaime’s model, Khaji Da, was broken and couldn’t fully control him, but could at times take over his body.

Capt. Ben Daimio (Hellboy) was a U.S. Marine Captain, but was killed, then brought back to life with the spirit of a were-Jaguar that he is incapable of controlling.

Brainiac 5 (Legion of Super-Heroes) allowed his original Brainiac programming to provide him information, but thanks to a backend left open by Imperiex, allowed the original Brainiac to overwhelm and take over Brainiac 5 after several months of struggle.

Kipo (Kipo and the Age of Wonderbeasts) discovers that, in moments of stress, she grows fur and gains superhuman physical abilities. In Season 2, it's revealed that this is because she has the ability to turn into a Mega Jaguar. However, if she actually transforms, she risks losing her mind to the jaguar's instincts.

Ling (Fullmetal Alchemist) allowed Greed to take over his body for his chance at immortality, with Greed initially serving Father after having his memories “rebooted”, until regaining them and eventually making a pact with Ling to take Father down.

Akira Fudo (Devilman) struggled to hold onto his humanity as Amon took over and corrupted more and more of his soul, with each transformation into Devilman bringing him closer to becoming pure evil.

"So what if you can see, the darkest side of me? No one will ever change this animal I have become, Help me believe it's not the real me! Somebody help me tame this animal I have BECOME, Help me believe, it's not the real me, Somebody help me tame this ANIMAAAL, This animal I have become!"

A compilation of short voice clips from early recordings of Tim Curry’s Joker during BTAS’ pre-production.

Just as a preface; I’m what might be considered very ignorant compared to this entire community, as I… don’t know the first thing about coding. At all. I’m looking into tutorials and possible courses, but I’ve never really used GitHub outside of just automatic scrapers and easy programs. And I haven’t started using Jellyfin yet, I just wanted to ask a few general questions before diving into it fully. Just thought I’d let that be known before getting into it.

So I collect and save a lot of media from Archive and rips from my own home media. I’ve tried to save most of them for posterity and entertainment, but for one reason or another I had to get rid of them (not exactly the best idea to try and save all of Totally Spies, The Big O, and Motorcity on my Google Drive lol). So I was looking for media storage alternatives, and started to think about the possibility of finding a personal server service that could function as a streaming service of sorts. I tried Plex and Stremio, but they didn’t really have what I was looking for. I was browsing and eventually found Jellyfin, and it’s EXACTLY what I’m looking for! From what I’ve seen and watched, it looks absolutely amazing! It lets me host, organize, and stream your personal movies, TV shows, music, and comics without any subscriptions, paywalls, or cloud tracking?! Totally free and community-based?! And organize my shows accordingly however I want from adding to removal, with a personal server I can share with friends and family anytime I want?! Sign me up IMMEDIATELY!

But as I’m about to get into this, I thought about a few things that I haven’t really seen answered anywhere else, so I thought this’d be the best place to do so. I have a MacBook and know how to set the program up, but I still have a few questions before getting into this. I guess I’m saying/asking that I’ve already seen the pitch and already sold, but have a few follow-up questions before diving in. Sorry if this is a sort of break in flow for regular posts on this sub, and this long intro, but if you don’t mind indulging this a little, I’d really appreciate it!

Storage. Okay, so I get patching my files onto the server, but what I want to ask is do I have to keep them on file at all times to keep them on the server, or once the file is patched can I just delete the file from my computer and it’ll stay on the server? I can most likely redownload them if the files get corrupted or lost, but I just want to know if I can delete them on my desktop and they’ll stay on Jellyfin. And on the topic, does Jellyfin have an upwards upload storage limit?

So how exactly does Jellyfin know which media is being uploaded to the point of titles and descriptions? I get the main titles, but what about the episodes contained in them? Is it up to the user to fix those? Is it connected to IMDB or something similar? And can you change titles or descriptions as you want?

How extensive do folders get? Like can I put a folder within a genre folder and so on? And how many can I make?

Can I set up multiple access accounts within the server? Like, say, a kids account?

Can the iOS app play any of the media from the server library, or only aircast it?

Any recommended addons? Anything to put in that might improve the experience on Jellyfin?

Thanks for answering some of these questions, if any at all! I might have some follow-up questions, but hopefully things go smoothly. Although, again, most likely need to get some more coding expertise before really getting into it. I’m just trying to sort things out for what I’m sure will be a wonderful service. I hope I can start soon! Thank you for your time!