The game recycles content from the original Mega Man for NES and its sequel, Mega Man 2. At the start of the game, only four robot master levels are available to choose, all of which are from Mega Man. The second four robot masters, all of which are from Mega Man 2, are fought as bosses in the Wily Stages of the game. This would become a staple of the Game Boy games until Mega Man V, the only Mega Man game for Game Boy not to recycle large amounts of content from the NES games.
The game is currently available for download in the Nintendo 3DS eShop.
Dr. Wily once again sets his sights on world domination. This time, he revives several of his Robot Masters, giving them another chance to do battle with Mega Man. Four Robot Masters rampage across the globe, so Dr. Light sends Mega Man out to stop them. Once they are taken down, Mega Man heads to Wily's fortress only to discover that four more Robot Masters await him there. To make matters worse, Dr. Wily has constructed a new powerful robot, a Mega Man Killer known as Enker. Enker has the ability to absorb Mega Man's plasma shots with his lance and return a powerful blast of energy at him with his Mirror Buster; however, Enker is defeated, and Mega Man chases Wily to his space fortress above the Earth, using Enker's own Mirror Buster to defeat him.
The game was originally called Mega Man World, also, the Rom had sprites with the word "World" in the title screen, but for unknown reasons the title screen was changed to only Mega Man.
The game has an unused track for the ending.
The concept of fighting 2 groups of Robot Masters (4 in each group) would later be used in Mega Man 7 and 8.
The title on the package is given as Mega Man: Dr. Wily's Revenge, but the actual on-screen title just says "Mega Man."
If you obtain Robot Leader weapons from the Mega Man 2 robots at the end of Wily's castle and end up dying before defeating Enker, you must restart the castle from the beginning, and you lose any weapons you have obtained from those Mega Man 2 robot leaders. This makes this the only classic Mega Man series game (and quite possibly only game in the entire series) in which it is possible to lose special weapons you have obtained.