With one exception, which is also making its way to the 3DS Virtual Console, all of the Game Boy Mega Man games take two of the NES titles and rework them a bit. Some old faces in new places, so to speak. A sprinkling of unique bosses and weapons help to carve out identities for these portable experiences but, by and large, the handheld games have been content to stay within the structural confines of the NES originals.
That's not so with Mega Man IV. Though two games are being mined for their resources (Mega Man 4 and Mega Man 5, naturally) this is the first of the Blue Bomber's portable adventures that attempts to evolve the classic series as a whole.
The surprising part is how well this works.
As with the previous Game Boy Games, the stages are split into two main groups. In the first group you'll find Pharaoh Man, Bright Man, Toad Man, and Ring Man from Mega Man 4, and in the second you'll find Crystal Man, Charge Man, Stone Man, and Napalm Man from Mega Man 5. It's worth noting that the remaining bosses from Mega Man 5 never made a Game Boy appearance, leaving us without a chance to see great evolutions of the original Gravity Man, Wave Man, Star Man, and Gyro Man stages. It's also worth noting, probably surprisingly, that it's the bosses from Mega Man 4 that end up receiving the best treatment in the entire portable series, thanks to their appearances here and in the also excellent Mega Man III.
You'll have to guide Mega Man through all eight of these stages, navigating obstacles, defeating bosses, and mastering the use of their special weapons. So far, so similar. The real delights to be found in Mega Man IV, though, are the things it does differently.
For instance, this was the first game in the classic series to introduce a shop feature. It's completely optional, but it will serve as an unquestionable boon to those who struggle with the game. While the levels are almost never unfair, it's certainly nice to have a chance to stock up on E-tanks and extra lives to make it through trouble spots. The currency here is P-chips, which enemies drop, and which would eventually be superseded by screws.
This is also the game that introduced intermission battles to the series, giving you a chance to square off against a powerful and unique enemy before moving on to the next set of Robot Masters. It serves as a nice breather, and helps to flesh out an already impressive experience.
On top of that, Mega Man IV introduces weapons demonstrations. In previous games you'd be granted a new weapon, and then left to your own devices. This certainly encouraged experimentation, but it also led to many players ignoring weapons that they couldn't figure out how to use properly. Here, every weapon and utility you collect is complemented by a short animation that gives some idea of how it's used. That prevents players from being hopelessly confused, while also allowing plenty of room for experimentation to discover the nuances.
Those are the most obvious evolutions to the classic series, and every one of them is welcome. As far as the main experience of the game goes, every one of these levels is at least as good as its NES counterpart, and a good argument could be put forward for every one of them being better.
Ring Man's stage, for instance, is no longer the home to an oppressive amount of mini-bosses. Bright Man's stage gains a few new platform types to figure out. Crystal Man's stage builds to an unexpected sprint through collapsing corridors. Napalm Man's stage finds a use for the completely unused quirk of the burrowing machines on the NES that allows them to serve as platform. Mega Man III took a lot of welcome liberties with the original stages, but Mega Man IV contains so many extreme improvements that apart from the soundtrack and level elements, these hardly resemble the original stages at all.
Other improvements include a massive amount of optional rooms and alternative routes to find, as well as a collectible letter in every stage. The Mega Man 4 robot masters all hide letters that spell BEAT, and collecting them will allow you to call upon the assistance of Mega Man's personal avian aggressor. Beat, however, is optional. The Mega Man 5 robot masters aren't so easy going, and you'll need to hunt down and find their letters to spell WILY in order to play the final level.
Additionally, while Rush Jet and Rush Coil both feature, the most useful utility comes in an unexpected form: the Ring Boomerang. A decent enough weapon already, Mega Man IV grants it the ability to collect items from a distance. It's an extraordinarily handy evolution of the weapon, and one that demonstrates just how much care was put into crafting an experience that could be remembered and appreciated on its own merits.
The Wily stages here are also the most interesting in the portable series yet, and they include not one but two encounters with the Mega Man Killer for this game: Ballade. The first fight with him isn't much to worry about, but by the time you encounter a beefed up version late in the game, you'd better hope you've honed your marksmanship. His weapon is the Ballade Cracker, which works something like an exploding Metal Blade. If that description doesn't make your mouth water, you have no soul.
Mega Man IV is a front-to-back excellent experience. Its difficulty might not be as high as Mega Man III's, but it's a more fair kind of difficulty, and it certainly puts up a good fight if you're willing to forgo shopping sprees. Best of all, it lays the groundwork for the crowning achievement of the Game Boy series...but that's a story for another time.
Mega Man IV represents improvement on its source material to an almost unbelievable degree. Alternate routes, optional pickups, a store system, completely redesigned levels and the meatiest Wily experience yet in the handheld series make this an unfairly overlooked outing for the Blue Bomber. This is the last of the Mega Man handheld games to remix NES titles, but it's certainly not the least, and it's a brilliant end to the tradition.