Dr. Straub
From the start of a game, Straub appears in one of several hidden spots of The Darkest Shore, only where no player is looking, and leaves when someone looks straight at him. Shooting him unlocks Still Lurking, for the player who shot him only. He stops appearing when the final boss fight begins.
Where to look
Among the known spots: the zombie window halfway up the stairs of the Beach Passage, the stranded submarine of the U-Boat Pens, the windows and the roof of the Artillery Bunker, the broken bunker next to the M1941 on the Overlook, and a doorway of the minecart tunnel facing the chamber of Nerthus.

