https://clips.twitch.tv/SpotlessSpinelessCobraEagleEye-NeumKmMtStCq6dE_
Darkness warning at 5 seconds remaining, with countdown and custom sound ft. getmilk.
Sound source: https://www.twitch.tv/laty1337/clip/CleanLuckyHamsterGOWSkull-vGfRpY9q7IDhw2EK
Requires custom sound downloaded and place into your World of Warcraft/Interface directory: http://www.mediafire.com/file/1h4ywfitq53eshj/darkness.ogg