Shotgun.

Background
Some years after the 1964 murder, a group of detectives and police officers armed with shotguns went on looking for the murderer but ended up being murdered by a killer armed with a machete, After some couple of years survivors desperate for salvation started finding these shotguns left from the ancestors of the investigation.

Trivia.

 * The shotgun has 1 shot and if it hits the killer it will kill him and he will respawn from the underworld.
 * It can be reloadable when ammunition is found.
 * First findable weapon without any form of payment.