Only positive quality is the retro nature.

an interesting and fun little game that's a call-back to the 8 bit age.
textures sorta remind me of minecraft, in a good way.
heh, the little enemies are silverfish...
yeah...

I found the game quite entertaining and challenging as well as the music complimentary. Also, as Sameezy said, the lack of jump (as well of the lack of ability to fall off ledges) was annoying at first, but it added to the game's challenge and fun. However, I have three pet peeves that I would like to mention in chronological order. First off is the starting keys. Once I click play, the game does not register that I am playing it, so I need to click again in order to use any keys to move. I think that your players will feel more at ease from the get go if you can just click play and move, without having to click on the game again. Secondly would be the music. In case of outside interruptions, once you start the game, it would be nice to be able to toggle the music on and off. Lastly, and I realize this is just a pet peeve and not really important to the gameplay, I find that it's annoying that Bitboy and the monsters can go between the stone door blocking the entrance and the door. I find myself questioning the logic of this many times as in real life, if I could pass between a locked door and the threshold it's guarding, I wouldn't run around trying to find keys in order to go through the threshold. But as I said, it is an awesome game and I look forward to playing your full game

Initially the lack of a jump mechanic got on my nerves, but I realised that the absence of one demands lightning reactions from the player, and after I got the hang of sprinting for ladders, I personally enjoyed the challenge! What brings this game down, in my own opinion, is the sensitivity of the controls! You can let go of the arrow key and still coast / slide into an enemy which is very frustrating when you get so far into a level! As well as this I have died when not touching enemies, merely being close to them, which is equally infuriating, when you need to be close to enemies to walk under them on the upward bounce.

Not to sound rude, but I'm having trouble playing at all. When the loading its complete and the screen appears. I can't seem to click anything on screen. Is there a possible reason for this?