Paper Airplane
During gameplay, press and hold the button you have mapped to PUNCH. After a second, Sketch will tear a paper airplane out of the backdrop and throw it, losing some health in the process. It will considerable damage all enemies it hits before boomeranging back off screen. Please note that Sketch can also get damaged by this paper airplane, and it does a large amount of damage to him.
Unlimited health
Hightlight and press C over sounds 3, 12, 17, 2, 2, 10, 2, 7, 7, 11 in the Jukebox.
