Concentration, Psionic (Con; Psionic)
You are particularly good at focusing your mind.
The following are additional uses for the concentration skill.
You must make a Concentration check whenever you might potentially be distracted (by taking damage, by harsh weather, and so on) while engaged in some action that requires your full attention. Such actions include manifesting a power, concentrating on an active power, directing a power, or using a psi-like ability.
If the Concentration check succeeds, you can continue with the action as normal. If the check fails, the action automatically fails and is wasted. If you were in the process of manifesting a power, the power points are lost. If you were concentrating on an active power, the power ends as if you had ceased concentrating on it. If you were directing a power, the direction fails but the power remains active. If you were using a psi-like ability, that use of the ability is lost.
The table below summarizes various types of distractions that cause you to make a Concentration check. If the distraction occurs while you are trying to manifest a power, you must add the level of the power you are trying to manifest to the appropriate Concentration DC.
Gain Psionic Focus: Merely holding a reservoir of psionic power points in mind gives psionic characters a special energy. Psionic characters can put that energy to work without actually paying a power point cost-they can become psionically focused as a special use of the Concentration skill.
If you have 1 or more power points available, you can meditate to attempt to become psionically focused. The DC to become psionically focused is 20. Meditating is a full-round action that provokes attacks of opportunity. When you are psionically focused, you can expend your focus on any single Concentration check you make thereafter. When you expend your focus in this manner, your Concentration check is treated as if you rolled a 15. It's like taking 10, except that the number you add to your Concentration modifier is 15. You can also expend your focus to gain the benefit of a psionic feat-many psionic feats are activated in this way.
Once you are psionically focused, you remain focused until you expend your focus, become unconscious, or go to sleep (or enter a meditative trance, in the case of elans), or until your power point reserve drops to 0.
Action: Usually none. In most cases, making a Concentration check doesn't require an action; it is either a free action (when attempted reactively) or part of another action (when attempted actively). Meditating to gain psionic focus is a full-round action.
Try Again: Yes, though a success doesn't cancel the effects of a previous failure, such as the loss of the power points for a power being manifested or the disruption of a power being concentrated on.
Special: You can use Concentration to manifest a power or use a psi-like ability defensively, so as to avoid attacks of opportunity altogether. The DC of the check is 15 + the power's level. If the Concentration check succeeds, you can manifest normally without provoking any attacks of opportunity. If the Concentration check fails, the power also automatically fails and the power points are wasted, just as if your concentration had been disrupted by a distraction.
A character with the Combat Manifestation feat gets a +4 bonus on Concentration checks made to manifest a power or use a psi-like ability while on the defensive or while grappling or pinned.
Synergy: If you have 5 or more ranks in Concentration, you get a +2 bonus on Autohypnosis checks.
Source: SRD 3.5 Combined Skills