[3.5/PF/Homebrew allowed] Multiple Personality Character?

[Fax Celestis]

Anyone know of a way to mechanically represent a character with multiple personalities, preferably based within existing mechanics? My wife has an...interesting character concept she wants to play, and I'm having trouble coming up with a way to make it work.

[Tebryn]

DIDS is a barely understood (or even accepted) medical diagnosis. There's no real reason for it to be represented via mechanics since DIDS is a completely mental and behavioral issue. Separate Identities wouldn't have separate classes or abilities for example. Role Play it, that's the proper course.

[Taelas]

You could take a look at the Dvati from Dragon Compendium.

[Fox Box Socks]

Synad. 'nuff said.

[Starbuck_II]

Anyone know of a way to mechanically represent a character with multiple personalities, preferably based within existing mechanics? My wife has an...interesting character concept she wants to play, and I'm having trouble coming up with a way to make it work.
Well, Alchemist have Prc that does. Master Chymist:"Master chymists become two personalities sharing a single body"
Mutagen Form:
A master chymist’s mutagenic form is an alter ego that has a different personality than her normal form, an outgrowth of the mental changes caused by the mutagenic potions she has consumed over the course of her career. The mutagenic form shares memories and basic goals with the chymist’s normal personality but goes about meeting those goals in a different manner. The mutagenic form is often ugly and monstrous and may even appear to be a different race or gender than her normal form; they may look as different as two unrelated people. Indeed, the mutagenic form often has his or her own name, and may attempt to maintain independent relationships and strongholds (though the alter ego’s limited time in existence often makes this difficult). The mutagenic form even has his or her own alignment (which is selected by the player, but must be different from the master chymist’s normal alignment). The change in alignment only affects the master chymist while in her mutagenic form

[Kuma Kode]

The rules for Possession/Channeling in Book of Vile Darkness/Book of Exalted Deeds could help, depending on the nature of the extra personalities.

[Xtomjames]

Take the Paranoid Flaw, and ask to take the Doctor Jekyll Mr. Hyde insanity from Rifts...

In most cases when I've played DID characters I used will saves after designating specific situations that would trigger a switch. Often things like switching emotions.

The will save would be a DC arbitrarily designated by the DM. However, if you want to be more in control. You can decided the DC for a switch based on a few factors.

10+:
*Level of Danger (CR of a creature or total CR of the creatures being faced)
*loss of hit points/subdual damage, (The more hit points lost the harder it is not to turn)
*Drunkenness

Scale 1-10 for emotional state. The more angry you are, or sad you are, etc the harder it is to save on the will save to keep from turning.

[Curious]

Be a Binder, use different vestiges for different personalities.

[TheRinni]

A fellow player in one of my D&D groups played a character with a dissociative identity disorder. For the most part, it was roleplayed mechanic. However, the DM did allow the character's individual personalities to have separate alignments.

If you're looking for something with more dramatic changes, you could always look into Complete Scoundrel's Mountebank PrC. It gives you multiple Alter Egos:
Starting at 3rd level, you establish an alternate identity. This alter ego has its own distinct physical characteristics, quirks, preferred clothing, and so on. At will, you can switch your form between that of your normal identity and that of your alter ego. This ability works like the alter self spell, except that you can assume only the appearance of your alternate identity.

[Bhaakon]

Can you tel us more about the character?

IIRC, there was an artifact in 2nd edition that allowed the operator to put two personalities in a single body. I'll have to look it up.

[Fax Celestis]

If you're looking for something with more dramatic changes, you could always look into Complete Scoundrel's Mountebank PrC. It gives you multiple Alter Egos:

Mountebank is a fantastic idea. I may just stretch it into a base class.