A precision striker
Combat Focus I
At 3rd level, you gain Weapon Finesse as a bonus feat.
In addition, you gain Sneak Attack which deals 1d6 damage. This functions exactly as the Rogue ability, except for the amount of additional damage dealt.
You add Precision feats to the list of feats you can select as a bonus feat. You must still meet the prerequisites of any selected feat, as normal.
Combat Focus II, III, IV, V
Each additional time you gain combat focus, your sneak attack damage increases by 1d6.
In addition, you gain a stacking +2 bonus on Stealth checks to avoid notice each time.