Uber Lurker

Uber Lurker is a hidden achievement/trophy featured in the Call of Duty: WWII Nazi Zombies map The Tortured Path. It requires the player to find and shoot Klaus Fischer.

To do this, the player must enter the vision mode within "Beneath the Ice" and search around the map. Eventually, the player will find Klaus somewhere within the map, appearing as an apparition. The player must shoot Klaus before he can disappear.