Rainbow Six Siege is Ubisoft's tactical first person shooter, first released in 2015 and developed from Tom Clancy's Rainbow Six series. Its music leans on tense orchestral cues to underline planning, breaching and close quarters rounds, and short excerpts like this one circulated widely as players recorded menus and trailers. Fans often pair the swell with callouts like enemy spotted in montage edits. The cue remains popular because Siege has a long lived competitive scene, so a few seconds of its theme instantly signals serious, coordinated play to anyone who knows the game.