It appears that you are using bounding box collision on the spikes which seems counter-intuitive to me. I would think the collision bounds should be triangular.
I love this game but I think there are way too many save poijnts to make this game challenging and I sometimes question the level design. For example, there are a lot of switches to remove blocks that aren't out of the way at all. You just keeping walking and hit down occasionally and open up blocks that you haven't even encountered yet. Just seems a little pointless.
Initially I was thinking that the game needed a map, but then again the original Zelda game didn't have a map and that was part of the challenge. Excellent game!
Bug: On the level selection screen, when you hover over a level that you have gotten less than 3 stars on, the preview panel on the right shows one more start than you've actually received.
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fixed R = restart :) Thanks!