You can play the classic game of “Snake” on almost any YouTube video. No one knows exactly how long this mini-game has been available on YouTube or even why, but users can play the game on any of the new video player interface.

To activate the game, hold down the left arrow key on your keyboard when watching any video with the new player interface. The game can be activated when the video is either playing or paused, and does not work on embedded videos. However, not every video, especially bright ones, are ideal to play on, as it’s hard to see the snake or flashing objective. Watch the video after the jump to see what it looks like and how to play. Snake can be played in both regular and full-screen.