Wait, there's a mystery to Metalman? And it is "mysterious"? Isn't that just being redundant? And why in the world did I stick an avatar art for professional composer Kenichi Maeyamada AKA Fan Remix Extraordinaire
Hyadain the first image here? While I'll admit that this seems like a total mess from the start, I guarantee I'm going somewhere with all of this. Hyadain is getting featured in the beginning because it was through one of his musical remix videos that tipped me off to the mystery originally, although not explicitly nor was it his intention.
~One of these things is not like the others,
One of these things just doesn't belong,
Can you tell which thing is not like the others,
By the time I finish my song? ~
Thinking back to Rockman 3; Dr. Wily's Last Stand, one boss out of the roster of rouges seem out of place. But to understand where I'm coming form, first some background information. The opening plot of Rockman 3 goes along as so:

click the buster for Part 1
In Part 1, I was able to provide information that could explain why Rockman is able to fight without worry of runing out of energy for the Rockbuster that isn't simply a result of game mechanics. The theory utilzing this information for the workings of Buster energy systems (with some edits for fluidity and compactness) is as follows: