I was toying around with this build...a dex-based Drow, wielding shortswords, with heavy investment in Ninja Spy, racials (assuming they're ever fixed), and a little PM to get Vampire. I cant seem to find a similar build post-EP already discussed.
With Vampire, there's a negative level on crit...Ninja Spy can add another negative level with a finisher. Throw in the odd Enervation, maybe a Life Stealing weapon, and that could add up to a lot of negative levels. Vampires don't get life-on-hit anymore though, do they?
On top of that, 25% incorp from Ninja, self healing via negative, and a lot of Dodge.
I was thinking this might be a late-bloomer build, when negative levels start to be more useful than just raw damage. Something obvious I'm missing?