d20Dwarf
Explorer
Macbeth said:Any wizard who kills enemies with a single, powerful strike and uses stealth could easily be an assassin.
Easily? Let's not go overboard.
20 cross-class skill ranks. Let's assume it's a human wizard with 7 skill points per level (2+4+1). To have 7 cross-class ranks in a skill you must be...*counts fingers*...11th level. You must also spend 40 of your 98 skill points on Disguise, Hide, and Move Silently. Not a particularly good option for a wizard that already needs to buy up at least 3 other skills to max every level. You're spending 42 ranks on Conc, Kn(arc), and Spellcraft, and 40 on these 3 skills. Ok, so it's doable, but by no means easy, and that leaves you only 18 skill points for other knowledge skills, craft (alchemy or construct), and perception skills. Then, after doing all that, you're going to stop progressing in spells (effectively) and pick up non-stacking sneak attack, uncanny dodge, and death attack with your ray of frost (natch).
I think some people are addressing the original poster sorta sideways. Prestige classes, ostensibly, were *not* designed to specialize certain character classes...theoretically. The designers always maintained that they were supposed to flesh out organizations in particular worlds...that's why we put ready-made organizations in the Path books for each class. Some even lamented their use as "better archer," "better tracker," and "better knife-thrower." Of course, it's much easier to design them mechanically, and much easier to fit them into every book under the sun. The original poster's idea is an intriguing one...what if there was an "assassin" prestige class that catered to all manner of characters, or at least one for each of the big 4 archetypes. Interestingly, I wrote a similar article for Dragon a few years back, although it wasn't quite the same. The enforcer class in that article was a little bit of "what about a thug assassin, rather than a stealthy one?"
Focusing on assassins also limits how people are thinking about the poster's original question. Think also of horizon walker, blackguard, or even Waterdeep guild mage (with emphasis on the first two words, of course