The Matrix Weapons mutator for Unreal Tournament Game of The Year Edition was effectively a set of Counterstrike weapons converted for use in UT GOTY, with an added feature of slow-motion, like in The Matrix. Turning on bullet time would slow everything down, giving the player superhuman speed and reflexes, with super-cool weapons.
It was a fun mod to play with.
Unzip both files from the zip file and copy them into your Unreal system directory. (i.e. C:\UnrealTournament\System) then fire up a text editor and open up your UnrealTournament.ini file, which is in the same directory. Find the [Engine.GameEngine] section and scroll down to the end of the ServerPackages entries. Add an entry like so:
ServerPackages=MatrixWeapons
Save and close the file. After that, you should be good to start UT and add the Smack’s Ultimate Gun Pack mutator to any match you like. Remember to bind a key for the slomo toggle!