How to show a character with multiple personalitites?

Question

To preface this, I have seen the question multiple personalities characters speech in text and I feel that my question is different enough, to warrant a separate question.

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In my book, a character has multiple personalities. In one, personality defining scene, whilst she is playing a game. her normal personality (Niar), is overtaken by the gaming personality (Suoti).

I have thought about changing the name straight away - but I feel that it is really disorienting for the reader.

Right now I have written:

"My name is Eben - who are you?" inquired the old man.

"I'm Suoti," replied Niar, using her pseudonym. Suoti was much better at games than she was.

My problem is now - how do I carry on, in a way that doesn't disorient the reader. At the moment the reader doesn't know that Niar has multiple personalities (she only recently entered the storyline). The book is written in the third person omniscient, so anything goes.

Should I continue using Niar, or Suoti, or another option, in the rest of the scene, and how can I do this whilst not disorienting the reader?

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EDIT

Due to some misunderstandings, I would like to say that this is not a case of dissociative identity disorder, rather a byproduct of a magical accident, so any points over the reality of the personalities interaction, whilst helpful and very much appreciated is not applicable to the question.

Answer 1

Write the switch-over, and then refer to the individual by the name of the active personality. That, or assign a group noun that all the personalities will respond to (e.g. if they treat each other as sisters, then the surname may be a common factor, "Miss Watevachezcauwd")

If this is a Third Person narrative (either omniscient or limited but with access to this character's mental state) then you use metaphor for the handoff

"My name is Eben - who are you?" inquired the old man.

Mentally, Niar stepped back. She wasn't the best at games, so it was time to bow out. "I'm Souti," her replacement replied.

Answer 2

I would write...

"My name is Eben - who are you?" inquired the old man.

"I'm Suoti," the younger girl replied.

You can dodge the question of identity by referring to the body's physical characteristics until it's apparent that the one body hosts multiple personalities.

Answer 3

I'm writing a similar story, and I deal with it by giving the two personalities the same last name.

When transitioning, it's always "Ms. Smith."

Answer 4

You could imply that some of her appearance changes; for example: "My name is Eben - who are you?" Inquired the older man.

A mystic gloom surrounded Nair. Her smile was vicious, and her eyes became serious. "I am Suoti."

You could also imply a change of scenery, like: The light dimmed, and a mystical aurora gleamed from Niar. "I'm Suoti."

This could, however, become a bit confusing, but the reader will eventually understand this change of scenery and personality.

Furthermore, you could have Niar talk about Suoti in 3rd person to make sure the reader understands the change of personality.

Answer 5

I feel drop hints, like when you write a scene imagine how both characters will act and make note of the difference between them. If for example a character switches part way then show a distinct difference based on their personalities.

As you said Suoti is a gaming personality so I am assuming they are more of the teasing type I would say not have Niar/Suoti give a name, but be ambiguous for example-

> "My name is Eben - who are you?" inquired the old man.
> 
> "Who am I, that depends who do you think I am, am I really that
> person, sometimes I could be me, maybe I'm someone whose to say you
> are really who you say they are a name is just label, but doesn't mean
> it matches the person." The girl replied playfully with a teasing look as she giggles at the old mans expense.

See there you don't exactly state who she is, but you express a personality instead, readers won't know if she is just being playful or if her words mean somthing more. Give the reply based on which ever personality is in control and how they would express themselves, consider if the personality treats themselves as an I or we? Do they consider themselves the same person or two different people. How would one's answer be different then the other.

Another way is to add a shift at some point for example.

> "My name is Eben - who are you?" inquired the old man.

> A shift seemed to appeared in Niar's eyes as she considered a reply. 

Your not stating it clearly, but your implying somthing changed, you can get the same effects with different ways like a pause or blank look before they answer. You can even add personal quirks like maybe Suoti plays with her hair as where Niar doesn't and Suoti tends to do that whenever she switches in.

Either show the sign in the narrative, dialogue or personality. You don't need to out right say, but do somthing that the read may find odd or can be seen as foreshadowing for it.