Don't get the santa hat unless you just want a hat for your worm. While it's tricky to set up, you can fly with the spikes as well. Try to get your worm going as flat as possible along the surface, than hold the button that would make him go up. You should start slowly rising. Then all you have to do is mash the spacebar and your spikes will rain death from above.
I didn't like it much, It wouldn't let me attack the freaking bosses. I read the instructuions and i pressed the freaking arrow keys, both at a distance and close range when he slowed down. and I pressed space. all i got to say is WTF?
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