A person's fps pseudonym (aka Xarkin). The name is impersonated by a few noobs, however there is only one real omgwtfbs.
Also short for: "oh my god what the fuck bull shit" (if you are new to acronyms)
omgwtfbs has killed <insert random noob here>
"omgwtfbs iz wall haxizoring!!!!!" - Random crying noob who got lit up.
"omgwtfbs change your name or you will be banned because we are such hardcore tools/pussies that we do not allow acronyms that insinuate swear words on our server: Pussies R Us." - Admin who got owned.