Poison Use: A ninja is trained in the use of poison and cannot accidentally poison herself when applying poison to a weapon.
Sneak Attack: If a ninja can catch an opponent when he is unable to defend himself effectively from her attack, she can strike a vital spot for extra damage.
The ninja’s attacks deal extra damage anytime her target would be denied a Dexterity bonus to AC (whether the target actually has a Dexterity bonus or not), or when the ninja flanks her target. This extra damage is 1d6 at 1st level, and increases by 1d6 every two ninja levels thereafter. Bonus damage from sneak attacks is precision damage. Should the ninja score a critical hit with a sneak attack, this precision damage is not multiplied. Ranged attacks count as sneak attacks only if the target is within 30 feet.
With a weapon that deals nonlethal damage (such as a sap, unarmed strike, or whip), a ninja can make a sneak attack that deals nonlethal damage instead of lethal damage. She cannot use a weapon that deals lethal damage to deal nonlethal damage in a sneak attack, even with the usual –4 penalty.
The ninja must be able to see the target well enough to pick out a vital spot, and must be able to reach this spot. A ninja cannot sneak attack while striking a creature that has concealment.
Ki Pool (Su): A ninja gains a pool of ki points, supernatural energy she can use to accomplish amazing feats. The number of points in the ninja’s ki pool is equal to 1/2 her ninja level + her Charisma modifier.
As long as she has at least 1 point in her ki pool, she treats any Acrobatics skill check made to jump as if she had a running start. At 10th level, she also reduces the DC of Acrobatics skill checks made to jump by 1/2 (although she still cannot move farther than her speed allows).
By spending 1 point from her ki pool, a ninja can make one additional attack at her highest attack bonus, but she can do so only when making a full attack. In addition, she can spend 1 point to increase her speed by 20 feet for 1 round. Finally, a ninja can spend 1 point from her ki pool to give herself a +4 insight bonus on Stealth checks for 1 round. Each of these powers is activated as a swift action. A ninja can gain additional powers that consume points from her ki pool by selecting certain ninja tricks.
The ki pool is replenished each morning after 8 hours of rest or meditation; these hours do not need to be consecutive. If the ninja possesses levels in another class that grants points to a ki pool, ninja levels stack with the levels of that class to determine the total number of ki points in the combined pool, but only one ability score modifier is added to the total. The choice of which score to use is made when the second class ability is gained, and once made, the choice is set. The ninja can now use ki points from this pool to power the abilities of every class she possesses that grants a ki pool.
No Trace (Ex): At 3rd level, a ninja learns to cover her tracks, remain hidden, and conceal her presence. The DC to track a ninja using the Survival skill increases by +1. In addition, her training gives her a +1 insight bonus on Disguise skill checks and on opposed Stealth checks whenever she is stationary and does not take any action for at least 1 round. Every three levels thereafter, the increase to Survival DCs and the bonuses on Disguise and opposed Stealth checks increase by 1.
