WARNING: this commands is binded on keys: P, O, I, U, N, G, MOUSE3, ALT! If you already have some commands binded on this keys - please change keys on commands that i wrote!
WARNING 2: cheats that sv_cheats 1 will enable gonna have tag [CHEAT]. Also, commands with tag [CHEAT] won't work without restarting, so firstly type: bind "alt" "restart", then other commands!
Ok, here we go! Firstly, open HL and then press button "~" (console). Then you can copy this commands.
EXAMPLE: bind "key" "command"
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1) bind "alt" "restart" (restarting your server/singleplayer game)
2) bind "p" "net_graph 1" (showing fps & other stuff)
3) bind "o" "net_graph 0" (deactivating net_graph 1 if enabled)
4) bind "i" "sv_cheats 1" (enabling cheats)
5) bind "u" "sv_cheats 0" (disabling cheats)
6) bind "n" "noclip" (enabling noclip) [CHEAT]
7) bind "g" "god" (enabling godmode - no damage) [CHEAT]
8) bind "mouse3" "impulse 101" (all weapons + ammo) [CHEAT]
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Now there's command how to change your field of view! You don't need to bind it or something, just type it once.
EXAMPLE: default_fov (number)
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1) default_fov 130
Good luck! Have a nice day!