Dr Edward Richtofen is a German scientist and central character in the Call of Duty Zombies storyline, first appearing in Call of Duty: World at War in 2008 and voiced by Nolan North. His erratic personality, dark humour and sudden shifts from calm to manic made his voice lines highly quotable among players. Clips of his laugh and exclamations spread through YouTube edits, streams and soundboards, where they became shorthand for unhinged genius. The sound remains popular because it is instantly recognisable to zombies fans while still working as a generic crazy laugh for others.