WTF?
The idea is ok. Create a platformer with 1 life that is nearly impossible yet possible.
The bad thing is, you didn't execute this idea very well. So all you have to do to kill a crab is jump on top of it? Yet 6 out of 10 times when you jump on it you die anyway!
This just pissed me off a lot. I could have a perfect jump on it and somehow I would die.