Latvind
This rifle appears on first glance to be a Mauser Gewehr 98 (GURPS Hi-Tech, page 111) in pristine condition and with a TL8 variable-power scope (+3 to Acc) attached. The stock is ornamented with stylized representations of e wind and breezes; the name ‘Latvind’ is carved into the barrel. Any sort of esoteric scan of the item will reveal that it is magical. Disturbingly so; magically or psionically aware people will come away with the accurate impression that Latvind enjoys killing things while at the same time recognizing that murdering people is wrong. This is actually odd, for anything that might resemble a “Spirit of the Gun.” Your stereotypical spirit of an item doesn’t consider it immoral to fulfill its purpose. Latvind does; it simply enjoys being immoral.
As for its powers: aside from being a Very Fine weapon that does not need regular maintenance, Latvind ignores DR and halves HP when calculating cover DR for purposes of overpenetration (GURPS Basic Set: Campaigns, page 408) only. In practical terms, this generally means that a shot fired from Latvind can blast through a person and hit the one behind him while barely slowing down, and can easily shoot through regular wood or light metal barriers. Latvind is thus eagerly sought-after as an assassination weapon.
Interestingly, it never stays in any one person’s hands for long.