Psychic Energy Points (3.5e Variant Rule)
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 Psychic Energy Points
Rather than having psychic skills deal nonlethal damage through strain, psychic characters have psychic energy Points (PEP), similar to the power points of psions, which reflect how much they can use their psychic skills. The default is d8 PEP per character level, although the GM may prefer d8 PEP per class level for psychics (and psychic prestige classes) and d6 or d4 PEP per level in other classes, making cross-class use of psychic skills more draining. Perhaps other classes don’t have psychic energy points at all, but suffer nonlethal damage (or some other form of strain) instead, giving the psychic class an additional advantage.
Strain from using psychic skills is marked off a character’s PEP. When the character reaches PEP 0, he may no longer use psychic skills. PEP recovers at the same rate as nonlethal damage: 1 PEP per character level per hour. A character recovers PEP and heals damage at the same time. The GM may allow characters with 0 PEP to suffer strain damage as nonlethal or hit point damage instead, increasing a psychic’s capability to use his abilities over a longer period of time.