[johndallman]

Nightmares [-5*] and Sleepwalker [-5*] are both mundane mental disadvantages with self-control rolls. They both appeared in Compendium I for GURPS 3e, and I suspect they probably originate in the first edition of GURPS Horror. There’s a related quirk, Sleeptalker, in Power-Ups 6: Quirks, and both of them go really well with Flashbacks.

To be a disadvantage, Nightmares have to be pretty serious. You suffer them every night; you make a self-control roll on awakening, and failure means that you’re down a fatigue point that can only be regained by sleeping. A guilty conscience is a cliched reason for having nightmares, but it’s a cliché because it’s plausible. If you roll 17 or 18, you are affected more seriously, and are at -1 to Perception and all skill rolls until you get a good night’s sleep. Nightmares with a difficult self-control roll is a major problem; the timescale makes it difficult to use as an Affliction, but as a curse or a brainbug, it’s nasty.

Sleepwalker is straightforward: the GM makes a self-control roll for you when you go to sleep, if sleepwalking would matter, and if it’s failed, you go roaming at some point during the night. You wake up if someone awakens you, or after 1d minutes of sleepwalking in any case. If you’re in unfamiliar territory, the GM may roll against your DX to see if you trip or otherwise have a minor accident; if you do, you awaken suddenly, mentally stunned. You are highly susceptible to mental influences while sleepwalking, although no details are specified: I might give -4 to Will to resist. If you have unusual movement abilities, such as flight or teleportation, you might use those instead of walking. Personally, I’d limit that to powers that you can use instantly, since concentrating enough to cast spells seems implausible.

The description of Nightmares offers the opportunity for the GM to play out things that happen in your dreams during the game. They should start like a normal scenario but gradually become horrific. The other PCs are, of course, not affected by any events in your dreams, but the GM can give them bonus points for playing their parts well, if the dream game takes a lot of play time. I’ve done this in another context, a Mage: The Sorcerer’s Crusade, and it was good fun.

Nightmares is a fairly common disadvantage option on published templates, especially for people who do a lot of killing, get involved with horrific things regularly, have undiscovered talents, or are trapped in a horror game. It’s also fairly common as an after-effect of encounters with psionic technology. Sleepwalker is very rare on templates, and is mostly associated with characters with psionic powers. DF 14 Psi has a semi-advantageous perk version of Nightmares, which is only any use if you fail your self-control roll, and suffer FP losses. Fantasy points out that lycanthropes may mistake memories of their transformation for Nightmares, and Madness Dossier has technology or drugs to cause either disadvantage. Powers points out that Sleepwalker can plausibly activate abilities, and Steampunk makes both disadvantages temporary results of Shocking Revelations. Nightmares are a possible symptom of PTSD in Tactical Shooting, while Thaumatology uses it in critical failures, magical calamities, and the Evil Eye. Ritual Path Magic has a ritual to remove Nightmares, for a few days, which would be very helpful if you'd been hit by an Ultra-Tech insanity beam.

These disadvantages are associated for me, because of another gamer who had both, plus Sleeptalker. In student days, with fellow-gamers sleeping on student room floors, he once sat up in bed, shouted “Natural 20! Yes!” and flopped again, silently. Wandering around in the night while asleep was routine for him. On a later occasion, he woke me up with an explanation that the table in my room had been stalking me, about to pounce – he was still waving it by one leg. Perhaps because of him, I’ve never used them on a character.

Have these disadvantages been important in your games?