you mean, the japanese version used different names. It's aquaman here.
he's such a pushover. Actually, all of them are on megaman 2. I just beat megaman and do the rest in pretty much any order- just making sure I have flash before I fight quickman and I usually beat heatman before I fight woodman.
megaman 3, is a bit more annoying. I used to start with snakeman, but I now start with magnet man. He's far easier.
MM4 has a well-defined cycle. I start with toad man because he's so easy. let's see here, then it's bright man, then... well, I forget the others. ot surprising- 46 robot masters can be tricky to keep sorted.