Your most dastardly devilish deviant.

[cabbagesquirrel]

I'm making a homebrew world full of intrigue and double crossing whilst the world is at war. So I need some cool ideas for my bad guys. Just interested in the bad guys you have been set up against or set against your players in the past and what made them 'the best', i.e. more memorable than your other ones.

[dukexx]

never actually been used, but been wanting to. a LBEG or BBEG that pretends to be a PC's long lost ma/pa. moral delimma, and much backstabbing opportunity.

[BRC]

I'm making a homebrew world full of intrigue and double crossing whilst the world is at war. So I need some cool ideas for my bad guys. Just interested in the bad guys you have been set up against or set against your players in the past and what made them 'the best', i.e. more memorable than your other ones.

Ive never actually DM'd before, but Ive thought of some preety darn nasty Evil guys, heres one, Warlord Kargolortz, He rides a big black horse, he wears big spiky plate armor, he weilds a giant axe in one hand like it was nothing and commands an army of vicious cutthroat mercenaries.
So the party corners him alone and rushes him and he...Casts a Still Spelled Fireball, drops his wooden axe, and Dimensional Door's out of his armor, proceeding to blast the party down with spells. Yes, Mister Kargolortz is in fact a sorceror, not only that but one who knows the value of surprise. The Party that was ready for fighting a big nasty warlord is now up against a sly and clever caster. At this point the DM should grin in an evil manner and drink some soda.

[reorith]

how about an npc
that for some reason
seduces/asks a pc to father a kid

the offspring is actually a reincarnation of a powerful mage/ancient horror/god/anything.

and hilarity ensues when the pcs learn of it are tasked with handling the problem before it is too late.

[ZeroNumerous]

Take PC X's sibling/mother/father/son/daughter/wife/husband/best friend/long lost cousin twice removed.

Turn this creature into a phylactery.

The party must kill him to destroy the BBEG's phylactery.

[Lord_Asmodeus]

Have an NPC (or if you can, a PC) who is "good" and gets everyones trust, and while they go about their quest trying to find out who the mastermind, in reality its someone who's been with them all along, facing peril with them and almost dying a dozen times, I've always thought this kind of character was just... evil and creepy, for someone to go to such lengths to fool you and then betray you at the end, CREEPY MAN.

P.S. and if there's like a paladin or something who uses "detect evil" on him (paranoid or just to be sure or suspicious w/e) give him like a "lucky charm" that was given to him by a friend/wife/mother/father/brother/sister or someone, and they always keep with them (always) that makes their alignment always appear good, unless you want him to be discovered for the purpose of your game or w/e.

[Stycotl]

coolest bag guy i've ever encountered was the one that started out as my pc's best friend, in the party, and over the course of a gazillion adventures, some of them just roleplay mini-encounters, after i had gotten to admire the other character, then he steered away from us and became our constant nemisis. but he was still cool, cuz he still had that charisma that he'd built up with us. and there was still that desire to like him, to persuade him to come back. then it turned out that he'd been setting us up from day one. i'm talking two or three years worth of campaigning with this guy. we didn't see it coming at all.

my dos centavos

aaron out.

[Witch]

This is my personal favorite.