It has nothing to do with UT. Onslaught is when you are a savage and go in beast mode and bring the damage. Onslaught is when you are in the act of slaughtering someone at something. IE. fighting, fucking, gaming etc.
Man that bitch thought he was gonna win but I brought the onslaught and threw a vertical 360 cockslap with my lumber and broke his jaw.

We was boxin and i went in beast mode and brought the onslaught and got a K.O.

Man I got me some tight pussy last night, son it was a onslaught.
by TSNB November 20, 2008
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A good game type for the new Unreal Tournament 2004, sure to bridge the gap between the soggy PlanetSide world and all the UT fans it stole.
PlanetSide got nerfed... time to play Onsaught...
by raZe February 20, 2004
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A noobed game type in Unreal Tournament 2004 that focuses on camping with vehicles. The people playing are usually autistic 11 year olds who can't speak english and have zero fragging skills.

also known as yawnslaught.
Final score on DM-1on1-Roughinery:
30 Player1
-5 OnslaughtNOOB

Player 1: "Haha, you suck 1v1. Owned."
by Player1 December 30, 2005
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1. A person who has no life, no skills, no brain and no clue.
2. A term used commonly around the world to describe a person who is hated by ALOT of ppl. Also see faggot, homo, dick head, retard, fucktard, moron, racist, asshole and idiot
3. A fucking gimp who hangs around TFC league forums complaining about rules of the league he doesnt even play in i.e. someone with absolutely no life
1. "Fuck I hate that stupid cunt Onslaught with an absolute passion."
2. "Fuck ur being such an onslaught today Darrin, stop being sucha fucking dick and die already."
by LP April 7, 2003
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aka. suckslaught, cocksucking cumcatching junior higher who finds homosexual pleasures in acting tough and badass online; a faggotnese who is a disgrace to asians

omg this weekend lets go jump that motherfucker onslaught.
by suckslaught season April 7, 2003
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FaGgot who play's TF and likes teh Penis
onsl wanna play TF with my Penis
by reflector June 2, 2003
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