So, I've been doing a lot of poking around for cool Rogue tech, most of which seems to already be listed here. I did, however, want to share a build that I'm real fond of. It's pretty much strictly a damage machine, although it remains extremely stealthy.
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Assuming LA Buyoff: Dark Dvati Rogue 4/Swashbuckler 15/Sneak Attack Fighter 1.
Goes Rogue 1/Swashbuckler 1/Rogue +3/Swashbuckler +1/Fighter 1/Swashbuckler +13 (and yes, this would incur XP penalties, but those are dumb and every smart DM I've dealt with has waived them, so *shrug*).
Notable Feats: Daring Outlaw, Craven, Maiming Strike, Martial Stance (assassin's stance, qualified for with a shadow hand item), Two-Weapon Fighting.
Notable Items: Bracers of the hunter + bracers of murder (combined into 1 item, costs 14.5k), gloves of the balanced hand, rogue's vest.
Weapons: Assuming custom items (or at least deriving the cost of unique magic item effects), take the +4 atk/dmg on SAs from the sword of subtlety (costs 20k by itself), add that to a manyfang dagger (total cost, 52k). Now, enchant a pair of those for each twin with assassination, deadly precision, and martial discipline (shadow hand). With GMW, you now deal 4d4+172 plus 17d6 SA with each stab, assuming a final Dex of 34. Your AB is +49, counting flanking, attacking a flat-footed opponent, and delivering a SA while hasted. Your final attack routine is +48/+48/+48/+43/+43/+38/+33, each attack dealing 4d4+220 damage, plus 17d6 SA. Sacrifice 16 of those to deal 1d6 SA damage and 8 Charisma damage. Now, do that again because both twins are full-attacking. That's a total of 14 attacks, avg. total damage is 3269 physical and 112 Cha damage. That's without counting the rerolls for the SA from the bracers.
The main issue with this build (and all Dvati builds, really) is that you need enough gear for 2 PCs. Still, if you can pull it off, this duo can kill pretty much anything around. Note that they still do 56 Cha to targets normally immune to SA, so they still kill pretty much everything in one round. With Darkstalker plus a ring of the darkhidden, they can sneak up on pretty much everything without Mindsight, and with a way to block telepathy (mind blank possibly) they can sneak up on them too. Targets who can't be flat-footed are the worst for this duo, since a decent chunk of their damage (about 64 dmg per hit) is lost, and they lose a bit of AB.
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