Scratching with a poisoned needle

[The Colonel]

Originally Posted by Lovewyrm

Sleight of hand as a combat skill :P

This was actually my immediate thought if you were doing this as a stealth attack - whether for assassination or more modern purposes. Given that almost all poisons take time to act, being able to disguise the attack as a bump or brush pass gives you time to spike the target and then make your distance before the symptoms start.
Otherwise, go with brawl or karate to land an otherwise unarmed attack that happens to deliver a needle strike. Expect armour to render such a strike irrelevant without some serious penalties.
Or just make like Ananais from The King Beyond the Gate and have the needles built into a set of cesti - again, using brawl but making it much less obvious what you've just done.

[Pursuivant]

Originally Posted by acrosome

Is there a RAW answer to what skill to use when scratching a target with a poisoned needle? Knife? Or Brawling? Or DX?

If the needle is built into gloves or claws I'd use Brawling skill (or its default to DX) to scratch in otherwise unarmed combat. Per RAW, that's the way "scratchers" built into cyberware poison delivery systems work.

If you're specifically slashing or stabbing with a needle built into some other object, like a Hypodermic, use Knife skill instead.

In a non-combat situation, use whatever Influence skill allows you to get close to your target then use Sleight of Hand to deliver the poison unobtrusively. Your target will almost certainly notice, unless they've got the Numb disadvantage or they're exited and distracted, so roll vs. Acting, Diplomacy, or Fast Talk to apologize for the "accidental" injury.

[Varyon]

For something like a needle mounted on a handle (including a hypodermic needle on a syringe, but then you're looking at a stab-and-inject rather than a scratch), you'd use Knife. For something like a sewing needle or bo shuriken, you'd use Brawling. For needles that are mounted on the hand in some fashion (such as on a ring or attached to gloves), you could probably manage with a grappling skill of some flavor. I'd still be inclined to call for an appropriate combat skill for a surreptitious stabbing (or scratching), but you'd use other skills to get away with it - Shadowing to get close to the target without getting noticed, Sleight of Hand to prevent anyone from noticing you're armed, Acting to play it off as an accidental collision, etc.

As others have noted, realistically even if a scratch is enough to get a proper dose of the poison it will take some time to have an effect, typically making poison a poor choice for tactical combat (it can be useful at the strategic level, potentially making minor wounds markedly more severe and also damaging OpFor's morale... but if it basically gives OpFor permission to ignore the laws of war, it may well backfire). But poisons that work at a tactical time scale (in seconds - or even instantly - rather than in minutes) are extremely common in fiction and RPG's, which can potentially make a poisoned needle a useful weapon.

[whswhs]

If you're not in a combat situation, you could use Physician. Doctors (and nurses, who also have Physician skill) learn to give injections, including doing so in difficult situations. Veterinarian could probably work took.

[acrosome]

The envisioned use is sort of what witches used to get accused of- covertly pricking a victim with a poisoned needle in a public place. Fantasy setting.

[zoncxs]

Originally Posted by acrosome

The envisioned use is sort of what witches used to get accused of- covertly pricking a victim with a poisoned needle in a public place. Fantasy setting.

That means its not combat, Sleight of hand skill would be used vs a persons Per.

[Pursuivant]

Originally Posted by whswhs

If you're not in a combat situation, you could use Physician. Doctors (and nurses, who also have Physician skill) learn to give injections, including doing so in difficult situations. Veterinarian could probably work took.

A DX-based roll vs. either skill would be entirely appropriate.

Veterinarian would actually be the preferred skill. Doctors generally don't have to worry about patients who struggle to avoid getting vaccinated and are in the habit of biting, kicking, or scratching back.

[Anaraxes]

Originally Posted by WingedKagouti

IMO Knife should generally only be used if the weapon has a handle and an edge.

Originally Posted by Refplace

Knife is called out to use a Pneumohypo in combat (Ultratech, p. 199)

Originally Posted by johndallman

Needles mounted in a handle are traditional tools for dissection, and I've encountered them being used as poisoner's weapons in fantasy novels. I thought that was what the OP was talking about; they'd handle somewhat like hypodermics, making Knife skill plausible.

The ice pick is listed under Knife skill in A Dictionary of Danger, p 20, among other kitchen utensils.

MA also seems to think knives and ice picks can be used in similar ways; indeed, the ice pick is used eponymously.

Originally Posted by Reversed Grip (MA111)

A fighter with a reach C, 1, or 2 thrusting weapon (typically a knife, spear, or sword) can invert his weapon and use an “ice-pick grip"

[WingedKagouti]

Originally Posted by Anaraxes

The ice pick is listed under Knife skill in A Dictionary of Danger, p 20, among other kitchen utensils.

MA also seems to think knives and ice picks can be used in similar ways; indeed, the ice pick is used eponymously.

The Knife skill itself (B208):

Knife (DX/Easy): Any rigid, hilted blade less than one foot long, from a pocketknife to a bowie knife.

The barrel of a hypodermic needle could be considered a hilt, and ice picks certainly have one.

Needles used by cinematic assassins (almost?) never have anything facilitating a proper grip that would let the use control them in the way a knife could be controlled. As far as I've been able to find, they're uniformly presented as very thin metal rods with a point, which would make Shuriken a far better fit as a skill to use, but that's only as a Thrown Weapon and not Melee.

Which is why I suggested that anyone who has actually trained using needles in melee combat would have a special DX/A skill called Needle.

[Varyon]

Originally Posted by WingedKagouti

As far as I've been able to find, they're uniformly presented as very thin metal rods with a point, which would make Shuriken a far better fit as a skill to use, but that's only as a Thrown Weapon and not Melee.

Which is why I suggested that anyone who has actually trained using needles in melee combat would have a special DX/A skill called Needle.

Shuriken can be used in melee, with Brawling, Karate, or DX (see MA223 and MA226). Indeed, Shurikenjutsu specifically notes that spike shuriken (which are the most similar to a "witch's needle") were often used as fistloads (MA195).