I made this level over a year ago and been playing the whole time (sure doesn't look like it.) I also have a new controller and it doesn't want to map the shoulder buttons correctly.
Since MMM doesn't have a Cross Wall or even a Mecha Dragon, how do I simulate the end boss? Hot Dogs on Crash Lifts seem to do the job more is need. I chose Astro Man as the boss because he stays above the beam of instant death, but dips down occasionally to get hit by the player. If the player chooses to use only use the Mega Buster only; it make for an interesting fight.
Ah yes, the change from what should have been Air Shooter to Time Slow. Something that has bugged me about MM (and RKS does it too) is that fact for the most part you never get to use all your acquired weapons against castle bosses. I think the time weapons have gotten short shrift I going to do what I can to fix that.