"Flatline" is a track from Welcome 2 My Nightmare that was released only as a bonus track on the vinyl edition of the album.
Composition[]
The song is an instrumental dark ambient featuring the sounds of a heart rate monitor. After 46 seconds, the monitor flatlines and remains that way almost until the end of the track. At the end of the song, a deep voice (probably the same from the end of "What Baby Wants") says "Steven."
The song can be seen as an answer to the song "I Gotta Get Outta Here". It is implied that Steven has fallen asleep and has died, meaning that he will be forced to live out his nightmare forever.