DLC Pack #1 contains four new weapons - a minigun, a "noob tube", a sticky grenade and a "BFG" - the latter of which was a big plasma weapon found in Doom and Quake.
DLC Pack #2 consists of three new deathmatch maps - "EDF Base", "LKR" and "Map 3", presumably for the game's multiplayer mode.
DLC Pack #3 includes 15 new single-player maps, arm wrestling, the "Impregnader" weapon and a karaoke machine.
#3 is the only one that sounds interesting really.
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