Enjoyed this game, it looked really cool and retro! It became a bit repetitive after a while though, due to lot of enemies and large levels with a very small amount of variation. Me and my son had a little speedrun contest, I won. ;)
At first, I didn't realise the darker tiles was impassable, I thought they were "grass" and I got really frustrated because my character seemed to brake as soon as I wanted him to step on it. Took longer time than I would actually want to confess before I realised my mistake there. xD
A good job, overall! :)