easy to get out of bag by spamming up arrow and right arrow

Made it to wave 21.
After about 10 waves I discovered that I could pop out of the "cell wall" and come back in from the bottom. I have to admit that this game amused my wife when she saw it (she's not a gamer) and we both enjoyed trying to figure out how this game worked. Its a fun little game, but definitely a one-time thing for me XD