A 2@1 swordsman with a monomolecular edge Breaking Blade uses Decapitation Strike and does a decent to good, but not excellent job. His opponent fails to block. The swordsman cuts off his opponents head in one strike.
A killing blow on an average person must do at least 15 intensities of damage (because 1@5 is the average damage value of ordinary people with 1@5 Stamina, Resistance, and Will Power and a 1@1 Density), 16 if it's instantly fatal. People in Starsong are going to have unusually high Resistances, though, probably low 2@, which will raise the DV an intensity or two, all other things being equal. That means your fatal shot probably has to do 18 intensities of damage.
Unless you have huge damage point bonuses or riders, to do 18 intensities of damage you must have at least a Lethal weapon; but you said your guy was 2@ SAL, so he could have a dangerous weapon since he has +DC to make his attacks lethal. Problematic, though, is that he has to roll at least 86 and be successful to get that 18 intensities, and with all the defenses Starsong residents have, he'd have to be much better than a 2@ to get that kind of chance to hit. So we're probably looking at a fatal attack, which means a lethal weapon +DC. A roll of 37 would give you 18 intensities of damage.
This assumes that decapitation is color. You could handle it as a B7@7 (?) Special Damage attack that took specific penalties against success but resulted in severing the head if successful; you'd then incorporate it into a (or one of several) weapon-dependent martial arts style. I would again make the damage roll-based, but the base for the attack lethal +DC for style, noting that the professional (or the 2@ MSV) would get an additional +DC to make it annihilating (die roll equals damage). I'm thinking you're looking at a -20 SM on the chance of success (to balance the high damage level), but you don't want even every professional successfully severing heads easily.
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GPS by holding it up to the night sky and letting it triangulate your position from the stars (If its familiar with the local stars),...
Not to say that it couldn't work that way, but I will note that the telephone location application that identifies constellations does not actually compare the images to a database--it determines the location and position of the phone itself by GSPS and internal sensors, and so based on which way you're holding it tells you what Google Stars says is there. It will work just as well in the rain; it won't work on a planet that does not have a compatible GSP system.
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It does have a Nurse program which is effectively a 1@8 Nurse for diagnoses which can help you figure out the most likely reason you have spots on your arm.
Ouch. Don't let a doctor hear you write that. Nurses do not diagnose; they evaluate, assess, and recommend care. The nearest they get to diagnosis is that a nurse practitioner will under the supervision of a doctor record a proposed diagnosis for the doctor to confirm, and will recommend treatment in the doctor's name unless the doctor states otherwise.
More on point for game purposes, the SAL of a medical skill is only half the battle. You also need the bias level. In this, you can distinguish diagnosis (@0) from treatment (@1). There is a list of what's covered in each bias level in the special tech skills section after T15@ in the book. It makes a significant difference: someone with 1@8 SAL treatment of temporal displacement disorders and scriff-related conditions (15@ stuff) is inherently 2@2 at splints, stitches, bandages, tourniquets, and simple prosthetics (2@ stuff). On the other hand, someone who is 2@2 at that 2@ stuff doesn't necessarily have any ability at even 3@ amputations.
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...as for the breaking blade we I would suggest the following:
It suddenly strikes me that what you're calling a "breaking blade" is probably the same as this from my sheet:
Monomolecular blade (T12@9): katana which can cut through practically anything, but it also erodes upon contact with stuff so that two good whacks at something and its practically useless until he sticks it in his scabbard (T14@2), and lets the blade re-crystallize. Damage: Annoying with varying intrinsic damage rider. On first cut it is Lethal, after every successful hit it drops one damage category until the blade is recrystalized in scabbard (which is a T14@2 device) taking 10 minutes.
Since the character could add as much as +2DC, that would mean that the blade would be annoying+annihilating on the first (twice bonused) strike, then annoying+fatal, annoying+lethal, annoying+dangerous, annoying+damaging, annoying+annoying, and then just annoying. My impression is that the "annoying" is what you get if you hit someone with the stick and the Use Monomolecular Blade skill does not work.
It should have a heavy sit mod against armor not made to stop a monomolecular blade. +30 perhaps. I know MJ will chime in.
The technically correct answer to that is not that the weapon is sit-modded against the armor but that the armor is not effective against the weapon. That's usually an incident-by-incident ruling, but for example it would be said that a Kevlar vest has, say, -20 against bullets (low because it doesn't protect extremities--you can still be shot in the head or the femoral artery) but only -5 against knives or Teflon bullets, maybe -10 against lasers, and no defense at all against sonics. Usually the recorded value is the cover value against "kinetic" attacks, which usually includes bullets and other missiles, melee weapons, martial arts hits, and kinetic force attacks (kinetic blasters, psionically generated forces, magic force attacks, non-contact martial arts attacks), but the referee is supposed to make note when a particular form of defense does not protect against a particular form of attack. The problem with using a sit-mod is that someone with a steel shield isn't going to have more than maybe -4 (I'm looking at 8% coverage of a 4@8 density metal) while someone in a full suit of bronze plate (95% at 2@5) will have closer to -24, but you probably want the blade to be more effective in cutting through the softer bronze than the harder steel. If it were to me to decide, I would suggest that all hard metal protections are reduced to half, all hard polymers to one third, and all soft metals, plastics, wood, and other soft materials (leather, cloth) to one quarter. I'd also say that many materials harder than hard metals (gem and sci-fi/fantasy materials) retain three quarters of their value. That, though, I would still keep as a case-by-case judgment--4@8 Mithril Chain (hard metal) might retain more of its value that 4@1 ruby dust blend armor (something I've never actually considered before, so you're making me think, too).
It also means that neither the attacker nor the defender will ever be one hundred percent certain how effective an unusual weapon will be against an unusual form of protection. If you swing a Starsong monomolecular blade at a Star Frontiers kinetic dampening field, what happens? Only the referee can really make that call.
Does that work for you?
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I hope this all helps.
--M. J. Young
