[dcx2]

Extensions are the highest level of kung-fu possible. There's basic kung fu, which doesn't even require gamedata, like my laser sight plugin. There's intermediate kung fu, which can use gamedata to call game functions, like resetting your ability meter in the infected release plugin, but it can't change things the game does on its own. Then there's advanced kung fu, which uses extensions like Left4Downtown2 and SDKHooks, like in my Undo Friendly Fire plugin where I completely block the damage from happening. Extensions can actively change the values that the game is using in real-time, not just after-the-fact. These are called "Forwards".

Extensions for Linux will require recompiling, because the insides of the Linux dedicated server have changed, and extensions need to know what the insides look like in order to change things in real-time.