I'm kinda wandering how many characters there have been who are either entirely or at least partially reliant on another person in order for their powers to function properly. Examples that I'm aware of include...
Firestorm: For those unfamiliar with this character and are confused why he's on the list, Firestorm is actually two individuals fused together into one. Though confusingly Jax doesn't appear to need a partner to live yet Stein needed to bond with a partner for at least an hour a week in order to stay alive. Anyway they were far more dependent on each other than just using super powers.
The Wonder Twins: Zan and Jayna who need each other to activate their powers.
Más and Menos: A pair of Spanish twin speedsters who have to make physical contact with each other to recharge their powers. The longer they remain apart the slower they become.
Cloak and Dagger: These two aren't quite as dependent on each other as others on this list. Rather than being completely useless without each other they're actually TOO POWERFUL without each other. Being around each other helps them manage their powers so they can control them... or at least that's what I've been told...
Venom: Sybiotes by nature can only exist in a Codependent relationship so of course Venom had to be included. Also Carnage, Anti-Venom, Scream, and several others of his kind.
Sister Psyche: This was actually a temporary codependent relationship. Shalice Tilman, the original Sister Psyche had to hijack a new body in order to survive while her old body was recovering in a hospital. Aurora Borealis (Aurora Scott) became the second Sister Psyche sharing a body with Shalice while she was recovering from her injuries. After returning to her own body she got married to Manticore (Justin Sinclair) and took his last name, Shalice Sinclair.
This is all from City of Heroes in case you were wandering. Not my characters. Though as the concept of multiple Earths exists within the game I actually did get permission from the developers to make my own versions of Shalice and Justin from an alternate Earth. For the purposes of this thread however I'll stick only to the official canon.
Lex Luthor/Brainiac: There was a short time after Brainiac was destroyed that he I guess partially rebuilt himself as a Lex cyborg basically fusing the two characters into one. During this time Brainiac would of relied on Lex for his own survival and Lex was made stronger, and I think Brainiac also cured his cancer. So for a while at least these two were in a codependent relationship.
The Mask: Similar to Dr. Fate, the Mask is actually a different entity from it's host... Without a host it's just a hunk of wood. Though this entity seems to actually to some extent act based on the desires of the host. Typically repressed desires the host wouldn't normally ever actually act on.
Dr. Fate: Again the less informed might not realize this character is actually two entities. Nabu is a supernatural entity that resides in the helmet and takes possession over anyone that wears it to become Dr. Fate. Kent Nelson is most often the one referenced as Dr. Fate but he isn't really in control when he has the helmet on. Really though anyone can put on the Helmet and become Dr. Fate. Nabu is far more dependent on a host than the host is on him. And I'm putting this last due to the fact that the host isn't actually gaining anything from this relationship. The host actually is giving up his or her freedom when they put on the helmet to become Dr. Fate because Nabu takes full control over the host's body. Without a host the helmet is totally useless.
Are their any other character's I've missed? Keep in mind I'm not including character who are often depicted as partners such as Batman and Robin or Rocket and Groot, only characters who quite literally need to be together for a specific reason related to their powers. I've also tried to list them in an order from most reliant to least reliant. These are characters who for specific reasons need to be with another character or entity in order for their powers to properly function.
I also want to clarify that characters with multiple personality disorder don't count. The Symbiote and Nabu were included because they have been established in fiction as actual living entities separate from their hosts. The Hulk and Bruce Banner however are the same person. Like wise Green Goblin and Norman Osborn are one character, yes he talks to his mask but the mask isn't actually a living thing, it's just a voice in his head.
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