I had some fun playing challenge 8. I was running around randomly and noticed one of the rabbits was solid orange. I decided to stop and investigate, but I suddenly dissapeared off the screen. Whenever I, or any rabbit were moving we were visible above the level, but when we stopped we would submerge. I was able to kill all the bunnies by just hitting them once and they would "touch of death" die.
I tried the level again and was still stuck in the ground, when I tried to fight a bunny he hit me and i ended up under in another completeley empty snowy hill area. I tried restarting the level and there was nothin. Restarted game and it was all good though; gotta love fun bugs.
edit: changed image host