In the new chapter of a story I’m writing, Twilight has a conversation in her mind with an alternate personality. At the time, she is not in control of her body, but rather the alternate personality is, although Twilight is looking through the eyes of her body. Amidst this, she has a thought conversation with her alternate personality.

Now, at the moment both sides of the conversation are in italics, with no quotation marks or anything other than standard punctuation. As it is now, neither side of the conversation has any dialogue tags. Now, since it’s in their mind, there can’t be any actions to go along with it or facial expressions or anything. The problem is, is that I usually use a mix of dialogue tags and action.

Also, since it’s in their mind, I feel using the term ‘said’ would be odd, considering neither of them are actually saying anything.

Anyway, I think the question I’m trying to ask is this—or rather these:

Should I break down and use the dialogue tag ‘said’ for the sake of clarity?

How do I differentiate between the two characters' dialogue?

For reference, this is how it goes now:

I see you found the mirror, Twilight heard in her mind. She figured it must have been other-Twilight. Of course, I wouldn’t expect less from Princess Celestia’s own personal protege, mocked other-Twilight.

H-hey!

Hey, what? You know, since I’m in control now, I might have a little fun.

Like what kind of fun?

Well, Rainbow Dash did come all the way out to Canterlot to save you...

R-Rainbow Dash?

I just feel that the conversation’s tone moves along at too fast a pace. Maybe I’m just imagining things, though...

One of the things I was considering was having Twilight's portion not in italics, but I'm not so sure...

Anyway, looking forward to your responses!

Dialogue tags, yes. Keeps people from losing track of who's saying what. I'd also find a way to split the identifiers; a fic I'm working on has our "Twilight Sparkle" and a "Regent Twilight Sparkle" as separate characters, so I'd be sneaky and use "Twilight" and "Regent Sparkle" respectively. It's still a pain, though.

Bold or italicize one of the Twilights

I see you found the mirror, Twilight heard in her mind. She figured it must have been other-Twilight. Of course, I wouldn’t expect less from Princess Celestia’s own personal protege, mocked other-

Twilight.

H-hey!

Hey, what? You know, since I’m in control now, I might have a little fun.

Like what kind of fun?

Well, Rainbow Dash did come all the way out to Canterlot to save you...

R-Rainbow Dash?

890595 I'm fine with using dialogue tags in general, but not about using 'said.' What do you think about that? Maybe I'm just being anal, but they didn't actually say anything.

890577
Keep them in italics just make them different colors and tell who is who at the beggining of said chapter.

890599 Yeah, that's similar to something I was considering, which was not italicizing Twilight's actual thoughts.

890603 Yeah, I'm not a fan of different colors, but dialogue tags that aren't 'said' might work.

890601
If its italicized and initially identified as thoughts, the 'said' will be understood by the reader. It's one of those words the reader glosses over, but may well miss if it's gone.

890603
I can't speak for anyone else, but I'd find color changes rather jarring.

Seems like everyone likes putting voices in Twilight's head, don't we?

How closely are the two voices linked? Are they two voices in Twi's head, or is one the real Twilight and the other some sort of intruder?

890609
Well if you are not a fan of said use answered, replied, shouted, gasped, thought, yelled, etc.
890614
They are not very jarring for me if they are subtle colors such as purple, red, or green. Just not yellow. NEVER YELLOW!

890614 Yeah, maybe I'll use 'said.' Maybe the problem is with me, not the conversation. As I said in my opening post, I like to use action to differentiate the speaker, only using dialogue tags to further dissuade any confusion. Because in this it really is just two characters talking to each other without moving, like I've read so many times as a bad thing to have, I have to be more creative in my use of dialogue tags.

890618 It's sort of an intruder, but not really. For one, Twilight created it, but then stuff happened, and now it's angry and it took over her body. It has the same voice as Twilight, albeit with a bit of a meaner tone.

890623
890624
Be very careful about replacing instances of 'said' with something else, especially when it's redundant or unnecessary. The editor's term for this rather common error is said bookisms. TV Tropes has a self-demonstrating article and I pulled this off Google; basically, it's a tool that can be used well, but only if done correctly and sparingly.

Voice of experience.

890648 Oh, I'm aware of that. Due to the fact that I've never taken an English class, the internet has become my teacher. And one of the things that keeps coming up is that fact. (FWI I am a native English speaker, though.)

890663
Excellent! The captioned cats shall lead us to something internet. It will be glorious.

Also, your predicament reminds me of a recurring theme in The Immortal Game. Chapter three touches on it, but the middle of the story is closest to what you've laid out here. If it's not your thing, forgive me, I can't help but throw this story around. I don't even know.

Also also, now I'm hearing drums. Make it stahp.

I would propose you use the usual dialogue tags (said etc...) but place the whole conversation in italics. At the start be explicit that the conversation is happening in Twilight's head, and then trust the italics to keep the reader in perspective thereafter.

Regards,
Dafaddah

890671 From reading the description, it seems it isn't quite what I'm going at. As one my readers pointed out, my story's actually eerily similar to the episode about Gary from Fairly Odd Parents. I'm sure my sub-conscious had something to do with that... I'm not sure if you've seen it, but Timmy had an imaginary friend and... stuff happened. You know what? I don't actually remember most of the episode. Either way, it's actually freakishly similar to that episode.

890624
I do believe there can be plenty of actions to go along with the dialogue, probably not on the voice's part, but on Twilight's part. Anything the voice says can invoke a reaction in her, both physically and mentally.
Also, to make the dialogue more assessable, I'd personally prefer quotation marks to mark off speakers. There is no rule or reason to forbid them for thoughts, and as long as they're also in italics there shouldn't be any confusion.

890648
Lastly, It might not be the appropriate place, but I have to get it out of my system: I think said bookism is a bunch of made up hooey disguising the real issue. The issues are:
A, misuse of vocabulary. If the word doesn't mean what the author is trying to say it becomes distracting and confusing, not to mention plain wrong. But using them correctly can add a lot, especially create brevity, which in turn is wit. After all, there is a reason why there exist so many synonyms for 'to say'.
B, overloading. A real-life person can't yell for an hour straight. He or she will only yell single sentences, while the rest of his or her words will come out much more straightforward, i.e. he or she merely says them. Or in other words, if there's emphasis on every single word and line, there is no word or line that stands out.

Dialogue tags for Regent, action tags for Twilight. This'll break up the talking heads, and should add some life to Twi's reactions.

If Twilight isn't within earshot with another pony, you could always have the one that's 'in control' of her body speak things openly, like a monologue, and have Real Twilight's responses in the form of italicized thoughts. This also hammers home the point that something/somepony else is in control of Twilight's physical faculties.

890577 Personally I use 'apostrophies' for thoughts, and "marks" for speech

890763
It's a label covering a host of other problems, true, but that's par for the course. 'Said bookisms' are just a subset of show vs. tell. It's still a good starting point to learn of those issues, at least for newer writers. Maybe not so for those of us who are a little farther.

890763 Twilight isn't in control of her body, though. Her alternate personality (other-Twilight) is. Other-Twilight is also on a train with Rainbow Dash and Spike, so she can't show that she's acting strangely. Therefore, she has to act normal, which means not moving around weirdly or stamping her hooves or anything. On the other hand, she is looking away from the others, so facial expressions are acceptable.

Twilight is looking through other-Twilight's eyes, though, and is essentially having an out-of-body experience. So she can't actually do anything.

Anyway, I edited it and added on to it and this is what I ended up with:

“I see you found the mirror,” Twilight heard in her mind. She figured it must have been other-Twilight. “Of course, I wouldn’t expect less from Princess Celestia’s own personal protege,” mocked other-Twilight.

“H-hey!”

“Hey, what? You know, since I’m in control now, I might have a little fun." other-Twilight gave a playful smile.

“Like what kind of fun?”

“Well, Rainbow Dash did come all the way out to Canterlot to save you...”

“R-Rainbow Dash?” If Twilight could control her body, she would have felt a slight red tint come across her face.

“Well, your mind is really quite boring, so I spent most of my time looking through your eyes—which, I might add, is also boring. The only thing that I actually liked were your interactions with Rainbow Dash. And now that I have control, and Rainbow Dash is here...”

“Y-you wouldn’t!” Not that. Not with Rainbow Dash.

“Oh, I would! Now, if you’ll excuse me, I have to go. This pathetic little body of yours is already tired.”

“No, wai—” Too late, Twilight was thrown out of the mirror, where she landed roughly on the hard floor.

891679
Two notes I feel compulsed to make on this:
First, I feel it should be Other-Twilight, capitalized, as it is part of a name.
Second, I'd assume this is written from Twilight's POV. Therefore she couldn't actually see herself give a smile. She could feel it however (assuming this is compatible with the rules you have established in your story), which I think would sound a lot more creepy.

892417 Except her name is also Twilight, and the 'other' part is only for clarity on the readers' side. Well, I suppose I could make her name the name of the spell that she was created by, but the only problem is, is that I haven't thought of a name for the spell.

There is more to the scene that I haven't posted that happens before their conversation. I go through all of the weird feelings of not being in control then. Though I will change it to "Twilight felt herself give a playful smile."