[DJDhan]

You mean you want to use Ctrl instead of LMB for firing?
There is a setting in-game in th econtroller settings menu. Redefine the controls there.

AND if you mean you want to detect when a player presses the Ctrl key, KEY_FIRE is mapped on the CTRL key and the LMB both. So you can use KEY_FIRE to detect if a player presses the Ctrl key.


EDIT: For a list of Keys that can be detected, CLICK ME.