Feat that gives an extra 1d6 to sneak attack

[Cheiromancer]

It seems like it should be hard to have both a good BAB *and* significant sneak attack damage. That's the biggest argument against making it a feat; if you do, then fighters and rangers and barbarians can get it. If you do allow it as a feat, make sure that it has SA as a pre-requisite. A SA of +3d6 means that at least 2 points of BAB have been sacrificed (assuming you get the SA from rogue levels), and then you could even allow the feat to stack.

Just make sure you don't allow the Rokugan ninja! The class is available as a free PDF here, and has a good BAB as well as sneak attack at every odd numbered level. This ninja is different from the one introduced in Dragon 318; there the sneak attack ability was replaced by a "sudden attack" ability which doesn't work while flanking. And the Dragon 318 ninja only has a moderate BAB.

If the possibility of sneak attack damage and a good BAB don't bother you, then you can do what you like, of course. But people will suspect it of being a little too munchkin-friendly.

 

[Scion]

sneak attack is pretty limited to begin with. A feat that granted +1d6 sneak attack doesnt sound very strong at all.

Trading a feat for it means you are giving up on something else, potentially much more useful That is a pretty significant cost.

 

[drunkmoogle]

DEADLY PRECISION [GENERAL]
You empty your mind of all distracting emotion, becoming an instrument of deadly precision.
Prerequisite: Dex 15, base attack bonus +5.
Benefit: You have deadly accuracy with your sneak attacks. You can reroll any result of 1 on your sneak attack’s extra damage dice. You must keep the result of the reroll, even if it is another 1.

There is a feat in the XPH that allows you to reroll 1's, and that's the closest you'll ever see in a WotC book.

 

[diaglo]

the 2000ed splatbook had a PrC Foe Hunter. one of the feats/special abilities was Rancor... which is very similar to sneak attack.

 

[Ridley's Cohort]

A Barbarian or Ranger would not be too powerful if they traded in a precious feat for +1d6 sneak attack. They have so few feats that are always giving up something very good.

Not sure if it would be a problem even for a fighter. Easy access to Spring Attack would seem to make an attractive synergy, but then you are wearing lighter armor and/or possibly underutilizing your high BAB iterative attack.

Seems like a good mechanical route to build the "Dex Fighter" that Celtavian wants to see (in that long recent thread).

 

[edventure]

Stuff I remember off the top of my head...

The Duelist Prc has Precise Strike class ability that stacks with Sneak attack. It was nerfed in 3.5 though. I preferred the version in Sword and Fist.

The Minds Eye web enhancements had a power called Find the Heart that also stacked with sneak attack. It was for 3.0 Psionics though.

Look up Sword of Subtlety, you want one, trust me. +4 to attack and Damage on sneak attacks only.