Strapped Balor... :confused:

[SpiderKoopa]

Ok, my DM and I have a dilemna. I have a 11fighter/6anti-paladin half-elf who just got an epic level demonologist to "strap" a balor to his soul. We're having problems figuring out exactly what this should do. So, if any of you have any suggestions, it'd be great.
Oh... and might I add, Tan'nari ftw!

[TheOOB]

Considering there are virtually no game mechanics that deal with the soul in the first place, altering the soul shouldn't do much.

If you really want, try treating it as a intellegant item with a high ego, It could have nice spell-like abilities, but it will try to take over the person if they are not suitably evil.

[Skjaldbakka]

There are rules in BoVD for possession that you might be able to modify for that purpose. I might be thinking of one of the 'fiends of 'classes though
(although that could probably be used too).

[fusama]

If you really want, try treating it as a intellegant item with a high ego, It could have nice spell-like abilities, but it will try to take over the person if they are not suitably evil.

Wow, that just reminded me of the character Ichigo from Bleach. I never would have thought of using the intelligent item mechanics that way.

[Merlin the Tuna]

As someone who hasn't ever read the Tome of Magic, this sounds suspiciously like a situation that calls for Binder levels.

[SpiderKoopa]

Well, we were thinking maybe a split personality (one balor dominant, the other the main character dominates, but both have a combo of the other)... Maybe using the living flames thing every so often, and maybe a boost to int, wis, and a neg to char. Balors sure aren't pretty. =D
I'm hoping maybe you guys like the split personality and back me up, there's an uppety psionic in the party that I'd like to mess with by switching personalities during a fight with him. >D (That still works in 3.5 right? I know it defends against psionics in 2e... <.<;; )
So, what kind of spell-like abilites? Immediately I think things dealing with fire and death.
Maybe a death spell here, a flame strike there?

[Nerd-o-rama]

Rules for fiendish possession of mortals are presented in the Book of Vile Darkness and the Eberron Campaign Setting, with the latter being somewhat more current. Basically, the character gets nothing, the demon occasionally gets a body to ride around in using its own mental traits in this system.

However, this may not be for you. Binders, a class from the Tome of Magic, sorta do this, although they mainly deal with Vestiges, the remaining cosmic shadows of once-mighty beings that were written out of continuity by WotC, rather than simple Balors.

Looking at your last post and what you have in mind, consider using parts or all of the Half-Fiend template, particularly the ability score boosts and the Spell-Like Abilities. The template comes with a +4 Level Adjustment however, and a significant boost in power over the rest of the party. That's why I say to raid it for ideas, rather than take it wholesale.