Fun Stuff
This is a great game and I enjoyed playing it.
The graphics and the music give it a fun, retro atmosphere. It definitely hits the low-fi mark. Reminded me of the kind of thing they had on the original Game Boy.
As people have said, the difficulty spikes when the one-block slippery cliffs come into play (although I guess that's why there's an easy mode). I eventually made it through by jumping as soon as I hit the tiles to get a distance boost, but sometimes the X key felt unresponsive on the cliffs (maybe it's my keyboard, or my slow fingers). Other than that, the gameplay was just right.
The story was minimalistic, and the ending made me smile.
Good job! If you made this in two weeks, I'd like to see what you could do with more time.