Batman: Arkham Knight, released in 2015, is the final entry in Rocksteady's Arkham series, built around fast, free-flowing combat where Batman strings together strikes and takedowns. The knockout effect heard here comes from that combat system, marking the point when an enemy is finished and drops out of the fight. Clips like this spread through gameplay videos and fan edits, where editors reuse short game sounds to give their own footage weight and timing. Its clean, heavy impact keeps it useful for action edits long after the game's release.