One of the most satisfying and least frustrating experiences on the NES
Though, deceptively simplistic at first, part of what makes this game so re-playable and fun is the strategic elements of it. You could say that it has a simple "fire-beats-grass, water-beats-fire" element to it, but what I discovered from watching other gameplay videos online is that there is no real set way of playing it. While certainly there is tremendous advantages to using the typically set strategies, I found some powers worked differently for others than the did for me. For example, commonly the noted weapon of choice for Air Man is the Wood Man's power up; however, as a matter of personal preference, I always seemed to do better with Quick Man's power up against Air Man. Going back and watching others' play-throughs, I was consistently intrigued with each players weapon of choice for different situations. There is not one way of playing Mega Man 2.
This being said, I would venture enough to say that I actually prefer Mega Man 2 over the Super Mario Bros. games. Now I know I'm in dangerous territory making such a statement, but when I look at the variety of gameplay that Mega Man 2 brings to the table when in comparison of my own experience with Super Mario Bros. 3, I found Mega Man 2 much less frustrating and memorable. Again it is always dangerous to tamper with the Mario brothers, considering how many secrets Super Mario Bros. 3 is crammed full with, but I can not deny that I experienced a greater since of satisfaction beating Mega Man 2 then I did with Super Mario Bros. 3. I know this is a matter of personal preference, so if you desire you can't completely disregard this entire paragraph.
Not only is Mega Man 2 one of the greatest platformers of all time, it is one of the most influential games ever created! Literally hundreds, if not thousands, of games have been influenced by the Mega Man series. From other platformers, to run n' gun games, there is an endless variety of clones and spoofs as well as continuous sequels. Even games that don't explicitly copy Mega Man's game mechanics still show signs that they are "under the influence." Games like Blaster Master and Duck Tales took an already proven formula and polished it even more (I was careful not to use the word "prefected").
Mega Man 2 is one of the greatest games of all time, and I am privileged to have it in my collection of classic games. It's easy to understand why Capcom continued to take an already proven formula and spawn an endless amount of sequels, yet this is where it all started. Mega Man was okay, but Mega Man 2 was "Just Right."