Interesting game, I wasn't sure if the double jumping was intended. The controls felt a little bit off or unpolished, what makes playing harder then it must be. But maybe that was intended to fit the old arcade style of the game.
I liked the idea that you only have one shot, until it's landed. Would have been interesting if you would have to collect the head again, but that would only be possible with less enemies and might change the games pace.
The tree man in the background is nicely animated, I only made it once to fight against him and then I didn't know why I died. Nothing seemed to have hit me, but I just shot one of his vines/roots with the head. Does it kill you to shoot the roots? Or did I overlook a root below me?
Definitively a good looking game and highly engaging, but the controls lessen the engagement.