Grab is an attack option on B370 similar but different to Grapple. Like grappling it uses DX or a grappling skill roll, and is thus a basic use of that skill which can't be bought up as a technique. It refers to grabbing objects instead of grappling people.
Grabbing is the state of having succeeded in a grab attack, while Grappling is the state of having succeeded in a grappling attack.
- in the latter case due to later Grappling is Mutual policies, it can also be entered into via being grappled
Mechanically a key difference is Grabbing uses the "usual penalty to hit the hand" regardless of the size of the weapon/object being grabbed.
- B400 notably states "This does not apply to grabbing a weapon!" in regard to Grappling and Hit Location, meaning the -4 to hit the hand is not halved to -2 for Grabbing.
This is contrast with B400's Striking at Weapons which uses different penalties based on weapon size.
The implication is probably that you are "grabbing the handle" (in the hand) which would explain why it's technically easier to "grab" a knife (at -4 to hit) than to "strike to damage it" (at -5) because handles are thicker and easier to target than blades.
Crunchwise, if Grab is thought of as a grappe, then the explicit -4 to the roll could be perceived two ways:
- -8 halved
- an additional -2 for Partial Cover atop a -2, with that base -2 being a halved -4
The latter probably makes the most sense: the idea that it's just as easy to grab a handle as it is to grab a hand (roughly the same size) but that it's hard to grab a handle which a hand is already wrapped around.
This more makes sense for "a small handle which a hand mostly covers" weapons like knives though. The concept begins to deterioriate with weapons that have a variety of possible handholds like:
- a longsword (the handle is "two hands" long, so if it was being wielded 1-handed near either pommel or crossguard there would be an exposed handhold)
- a staff (where you could conceivably grip many parts not covered by a hand, with some giving better leverage than others)
The variety of possible handholds furthe expands for bladed weapons (which you normally would not grip barehanded) for those with natural DR or hand DR given by gloves/gauntlets since this allows gripping a sword by the blade with reduced chance of cutting oneself.
- halfswording explicitly uses this to get a shorter-than-usual reach for thrust-impale attacks but has not yet been explored in GURPS
- a murder stroke (aka Mordhau aka Mordstreich aka Mordschlag) also involves intentional blade-gripped attacks for the purpose of delivering swing-crushing attacks