cscommands.comglobal_set
global_set <globalname> <state>: Sets the state of the given env_global (0 = OFF, 1 = ON, 2 = DEAD).
For this command to work you must first run
sv_cheats true in the console. It only works on a local map or a private server — not in matchmaking. sv_cheats is a built-in Valve command and is completely safe from VAC.