I find that using my custom code that sometimes when monster entities do something (like, turning their head away from player, or trying to find a clear shot at the player, or others) that, for no clear reason, a spark would appear above their heads. I have no idea why this happens, I find this does not happen in normal HL, or any other game I believe. Since it happens on alien grunts, barneys, human grunts, scientist, so far, I believe it's some sort of bug caused by a base class. Do you all have an idea what is up?