So, since I am playing a 500 point badass in a GURPS game - what happens when I make a called shot to the groin with a 9d pi sniper rifle?
I am talking 20-40 damage. To a normal human bad guy.
So, normal human bad guy with only 10 to 12 hitpoints.
Depending on the realism of the game I'd have to say that you can't do that much damage to a dude's groin. It's just not a vital enough organ that taking it off is going to result in instantly death. It would be gruesome, that's for sure.
Of course, GURPS doesn't have people instantly die unless they get to some multipul of their HP in negatives. They do have to make the Health Test to see if they stay alive though.
If you did 20 damage, I would describe the bullet splattering the crotch area and the individual either curling up in an attempt to control the bleed (if he made his check) or his eyes rolling back and crumbling into a heap (if he failed it).
At 40 damage, depending on the tone of the game, I think the bullet would have to hyper-decelerate, imparting maximum impact force, shattering the pelvis bone and likely rupturing any and all internal organs stored within such as the large intestine, the bladder, and possibly the liver.
Any higher than that and he's basically cut in half.
Addition-
If gruesome is the goal than at high damage levels, again using the hyper-decelerate explaination, the bullet could catch his tail bone, ripping it out his back and creating a "rip" at the bottom of the dude's body so that all his vital elements dropped out (since his pelvis and hips shattered from the decelerate force they aren't there to hold anything in) and his liver and other guts would be dangling from his intestines. And if he makes his Health Test than he lives long enough to look down at the mess before dying.