Refining the formula.
This is it, folks: the game fans generally point to as the beginning of the original Mega Man series’ downfall. It’s certainly difficult to see the direct parallels between this genuinely good Mega Man game and the atrocity that is Mega Man 8, but Mega Man 4 definitely feels different, at a gut level, than its direct predecessors. Maybe it’s the longer stages or the addition of the chargeable Mega Buster, but Mega Man 4 marks a sort of turning point in the series. I’ve waxed nostalgic on this before in my review of Mega Man 10, which felt more like homage to the gimmicky second half of the NES series than the tougher first half.
Yes, Mega Man 4 introduces the chargeable Mega Buster, but don’t get too excited. It’s not as powerful as it becomes in the next game, and there’s little strategic reason to use it over normal peashooter shots in most situations. Mega Man 4’s biggest contribution to the series is significantly longer stages replete with unique segments. For example, in Pharaoh Man’s stage, you initially fight through quicksand. In Bright Man’s stage, you cruise on the backs of robotic grasshoppers AND change the lighting by shooting different enemies. Drill Man’s stage has platforms made visible when Mega Man hits switches, Toad Man’s stage is filled with flowing water that restricts your movement, and Dive Man’s stage—while underwater—features a constantly changing water level that influences your ability to jump over spikes and obstacles. A lot of really good level design is present here, some of which may encourage your use of restore points.

The bosses are more ridiculous than they’ve ever been, the result of Capcom asking fans to design all eight for the game’s development. As a result, Mega Man 4 features such oddities as Skull Man and Toad Man. Interestingly, using the correct weapon against a given Robot Master is no longer an automatic win; you still have to know what you’re doing because the given damage isn’t as great anymore. Other bits of innovation in Mega Man 4 include the addition of “Flip-Top Eddie,” a little robot that gives Mega Man a random item once in a stage, and two hidden items you must find. The only real disappointment is that the final “castle” stages are surprisingly easy, as are the bosses of those stages. Even Dr. Wily, who has three forms this time, goes down with little effort. I think the toughest part of the game is dealing with the Robot Masters, who have highly damaging attacks and good resistance to even the weapons they’re weak against.

So while there’s nothing inherently wrong with Mega Man 4, and it’s certainly not my favorite, that doesn’t mean it’s not a good game, because it totally is. It’s just a little different.