This seems pretty quaint nowadays, considering Bieber branched out pretty far from his teen-pop origins in the mid-'10s.
The bottle, knife and shuriken all hit to the left of where my mouse is, which complicated aiming for me a fair bit. Combine that with Beaver's erratic movement and the travel time of every weapon except the handgun, and you've got a pretty difficult target to take down. Still pretty fun, though.
(Sidenote: The handgun looks to be based on a CZ-75, but I can't pinpoint what the rocket launcher was based on.)