Mega Man was always the type of game you could pick up and play. Capcom has created the franchise for many different systems, starting with the NES.
They made 6 games for the NES each one adding something new. It wasn't until the third game that Megaman could slide and the fourth he could charge his shots.
Nintendo definitely got the most love from Capcom but the Sega Genesis was given the first three games from the NES series all in one package. It was remade with sharper graphics and more color but that was the end. Super Nintendo got Mega Man 7 and then started the X series. There were three of them.
Mega Man 64 got low scores for technical reasons but it was another great experience for Mega Man fans. I enjoyed it almost as much as when Sonic had his first good 3-D conversion with Sonic Adventure. After the series got beat to death on the Sony Playstation, Capcom came up with another great idea with the Mega Man Battle Network. While everyone was playing Pokemon on their Gameboys, I was playing Battle Network on Gameboy Advance. So very addicting.