give it a 3d model thats pitch black (with no shine maps so it looks flat) with white eyes, make it climb up tall walls instead of jumping up them, crawl through tight spaces, jump across gaps, and crouch through less tight spaces, then just to mess with the player, it opens and closes doors that the player doesn’t see but in audio range of the player, As well as opening doors just behind the player. Maybe even allow it to see what friendly npcs are in the map and mimic some of their sounds like the predator. Might not be possible, but when stalking, in a certain radius all animal based ambient noise dies(to simulate how animals go silent when a predator is in the area).