This is a purely visual effect which shakes ALL player’s screens (not just the one who triggered it) in a radius around it’s origin.
"ltime" key sets the total duration the screenshake will last, with the amount of shaking diminishing over time.
"multiplier" key increases or decreases the initial strength of the shake; n > 1 increases and n < 1 decreases. Defaults to 1.
"lip" key specifies how often the engine should update the screen, as a fraction of frames per second. So a value of 1 means 1 screen update per second. A value of 0.1 means 10 updates per second, 0.05 means 20, and 0.01 means 100 (or as fast as it can). Defaults to 0.01.
"height" key specifies how large a radius to affect player’s screens.
"noise" specifies the looping sound to be played while the entity is active and
"noise1" specifies the sound played when it ends. Set both to misc/null.wav to make the effect silent.