I like the art style and the run/shoot combination
--But you were right, this game is HARD! As of press time, I can't get past the S-curve on the 1st level of world 3, even though I have the best possible armor, shoes, weapons, and upgrades available. The fact that the worm "rubberbands" right before that section just makes it seem like you enjoy watching people suffer.
Also, I like the fact that after you've collected coins (and completed the level) you don't have to go back and get them, i.e., you don't have to have a single run where you collect every coin in a level. That's nice.
I'll keep trying for a bit more, but I don't know if I'll ever beat this game!
Good work!