Halo Reach is a first-person shooter developed by Bungie and released in 2010 for Xbox 360, serving as a prequel to the main Halo trilogy. Its multiplayer modes award medals for specific feats, announced out loud by longtime series announcer Jeff Steitzer. Killjoy is awarded for killing an opponent who was on a killing spree of five or more, making the call a familiar reward for defensive plays. Clips of Steitzer's medal lines were later shared widely as standalone sounds for gaming videos, streams, and meme edits built around stopping a streak.