My top 3 are 2, 1, and 6. In my opinion, they are the best games to get newcomers into the series and never get sick of them. They had music that you could listen to for days on end without changing the track. Megaman 2 also let you control the difficulty so that any newcomer could come in easily, and any veterans could get a decent challenge. Megaman 1 also put up a challenge that was beatable, but difficult. Megaman 6 took all the things that made 1 and 2 awesome, and added even more, like the jet pack and power adapters. It also made use of the mega buster (the chargeable P-shooter) and slide power up, moreso than the previous ones.