Night Terrors (3.5e Flaw)
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 Night Terrors [General]
Your nightmares run so deep, that they still haunt you upon your waking hours.
Effect: Each time you sleep, roll a d20. On a 10 or greater, you awaken prematurely and are plagued by the terrors the beset you while you slept. Upon awaking you are immediately attacked by some monster that lurked within your last dream, whether it is a dragon or a demon, or an army of orcs. However once somebody gains your attention, these phantoms immediately vanish and so do all of your wounds. If you are not awoken from these terrors, they last until they are defeated or you are. Once either of these things happen, you finally return to reality.
Roleplaying Ideas: The character with this flaw probably had some major past trauma to induce such dreadful nightmares; whether they have blocked it out or it haunts them still.