Those rotation buttons are oriented strangely. I usually think of clockwise as the arrow on top pointing to the right, not the arrow on the bottom pointing to the left.
You don't even need the fuse valve. One steam cannon is enough to take out the boss. One boiler controls the steam cannon, the other just makes you duck. I wish there were more enemies, weapons, and mechs...
Way too easy. Also, why the hassle of having to manually sell obsolete bows and arrows? You're never going to use the old ones after they've been upgraded. Anyway, there are much better games of this type out there, such as Elona Shooter.
Four of the most mind-numbingly boring levels I've ever played. The music is annoying, you spelled "Mario" wrong in the title, and the gameplay is the opposite of fun. Was this made by a little kid or something?