Thanks for the comments.
Toning down the mushrooms would probably do a lot to help the characters pop out more. It's too late for me to fix this up for the challenge but, maybe I'll revisit this at a later date. Ditch the low color count and do this piece a little more justice. I spent five hours straight on this, working 'til four in the morning, so I wasn't all that with it by the time I finished.
As for the premise of the piece; I started out with the idea that I'd remake the game with a theme more fitting to the tripped out comic that it spawned from. In the end it just turned out into an amalgamation of whatever I felt likes. heh.