Geometry Dash sixth major update included a new level called Clutterfunk, which used Waterflame's song of the same name. The size portal introduced a new game feature that made the player smaller. DJ-Nate wrote the title tune for the new level, Theory of Everything, which was included in the sixth major update of Geometry Dash. Additionally, the UFO game mode was added, which increased the speed with each press. The game Flappy Bird could have served as the inspiration for this. Purple jump rings were also added by Theory of Everything, which resulted in lower leaps than those made with yellow and blue jump rings. Although no Demon levels were created until 1.6, this update also included a new "Demon" rating for custom levels.