Capcom just flipped the sprites. In other words, lazyness.Or to save space.
The 'power' of the mega buster.Since some of the original 6 Robot Masters would flinch after you hit them with it, I suppose you could interpret sequels as having a less powerful version. Or, it could just be poor dialogue. At least it can shoot through walls, unlike the Bass Buster.
That thing is a joke.
He seems to be ambidextrous. In some official art, he is seen using his LEFT hand. in others, he is seen using his RIGHT hand. And both arms have the same design.
It's whichever hand he wants it to be.BINGO! Because both hands supports the Buster.