The use of the theme is a little bit of a stretch for me. "Scale the mountain" could just as easily be "Climb the mountain" and "Scale your character" is just upgrades or equipment. The level design isn't very engaging, the best option usually is to sit on the level of platforms below and jump/shoot so as to stay away from enemy bullets safely, which gets old pretty soon. Platforming isn't great, I personally am not a fan of the jump and switch directions in midair to progress. The art is really really cool!