Half-Life Sven Co-op

Half-Life Sven Co-op cheat codes: 
Load game with the command line: hl.exe -dev -toconsole.
Then, press [~] if the orange text on the screen does not disappear.
During gameplay, press [~] to display the text prompt and type in sv_cheats 1.
Press [~] and enter one of the following console commands to activate
the corresponding cheat function. Note: You can only use cheats when
the maximum players is set to "2".
godmode [0 or 1]               - Toggle God mode
giveall                        - All weapons
cl_noclip [0 or 1]             - Toggle no clipping mode
character cl_notarget [0 or 1] - Toggle opponents ignore