Mega Man Anniversary Collection a compilation of video games developed by Atomic Planet Entertainment and published by Capcom. It was released exclusively in North America on June 23, 2004 for the Nintendo GameCube and Sony PlayStation 2 (PS2) and on March 15, 2005 for the Microsoft Xbox. Mega Man Anniversary Collection contains the first eight games in the original Mega Man series, which debuted on the Nintendo Entertainment System (NES) with the first six games, moved to the Super Nintendo Entertainment System (SNES) with the seventh game, and then moved again to the PlayStation and Sega Saturn with the eighth game. The plot follows the robotic protagonist Mega Man in his continuing adventures battling the evil Dr. Wily and his army of Robot Masters.
Each game has a nearly identical gameplay structure in which the player traverses a series of themed stages to face off against boss robots, gain new weapons and abilities, then defeat Dr. Wily in a final confrontation. An extra feature is the "Navi Mode" for the first six titles, which provides hints and pathways for completing each stage. In addition to these eight games, Mega Man Anniversary Collection includes two unlockable fighting games (Mega Man: The Power Battle and Mega Man 2: The Power Fighters), which were both previously unreleased outside of Japan. These two titles are similar in gameplay but a bit more streamlined. The battles cut straight to the bosses, who get progressively more difficult with each one defeated. Other unlockables in the Mega Man Anniversary Collection include original artwork and remixed music.
Source: Wikipedia, "Mega Man Anniversary Collection", available under the CC-BY-SA License.