Mortal Kombat II Unlimited is a full scale hack of the Sega Genesis Mortal Kombat II game, Originally work on the hack ceased with version 07, but in 2011 version 1.0 was released which added many new graphical features. Added a combo system;Secret fighters now fully playable;Bosses now fully playable;More new sounds;New Select Screen and Main Menu;New stages and music from Mortal Kombat 1;New moves such as Brutality;New Game Modes such as Practice and Endurance;Returned biographies/Endings/Intro/VS-screens from the arcade version;and many more…

Motobug the Badnik in Sonic the Hedgehog (aka Motobug in Sonic 1) is a hack of Sonic the Hedgehog for the Sega Mega Drive, by Polygon Jim. As its title suggests, in this hack the main character Sonic the Hedgehog is replaced by Motobug, one of Dr. Robotnik's badniks.So far, some of Sonic's main sprites and animations have been replaced by those of Motobug, Motobug's speed has been decreased (except when powered-up by aSpeed Shoes monitor, which are more numerous), and the sprites of Roller badniks in Spring Yard Zone have been replaced by those of Sonic (referencing a common interpretation by fans that Roller is a robotic impersonation of Sonic, something that officially appeared in later games in the form of Metal Sonic and various others).Of the first release, Polygon Jim stated that he had only tested and confirmed Green Hill Zone (Acts 1-3) for completability. However, upon testing, Katelynn andRGamer2009 reported that other Acts are completable, including:Marble Zone Act 1Spring Yard Zone Acts 1 and 2Labyrinth Zone Acts 1 and 2Star Light Zone Acts 2 and 3Final Zone

Mr. Needlemouse is a hack of the original Sonic the Hedgehog game for the Sega Mega Drive / Genesis, by MKAmeX. It replaces Sonic the Hedgehog with one version (arguably the strangest) of his designer Naoto Ohshima's early prototype of the character, Mr. Needlemouse. Planned features include a complete overhaul of the game's graphics to resemble early concept art, and perhaps new music.

Mr. Nutz is a side scrolling, 2D platformer video game published by Ocean Software. It was first released for the Super Nintendo Entertainment System in 1993[citation needed], then later released for the Mega Drive and Game Boy in 1994[citation needed], then Sega Channel in 1995, followed by Game Boy Color in 1999, and Game Boy Advance remake in 2001. The player controls the one player character, Mr. Nutz an Anthropomorphic red squirrel wearing shoes, gloves and a cap through six themed levels. The end goal is to stop Mr. Blizzard, a yeti, who is the final boss and is trying to take over the world by using his magic powers to turn it into a mass of ice. The game shares similarities with other platformers of the same time, being that jumping is the main technique used in the game to navigate both fixed and moving platforms and defeat or avoid most enemies. Ammunition, in the form of nuts, can be collected and thrown at enemies. Ocean released in 1994 another game on the Amiga under the name Mr. Nutz: Hoppin' Mad. Developed by Neon Studios, it featured the same titular character but with different, faster and more wide-open gameplay, unrelated levels and enemies, another story, and a large overworld map instead of a linear path to follow in a mini-map. This game was also going to be released for the Sega Mega Drive in 1995 as Mr Nutz 2, but it got shelved. A playable build exist, leaked in the form of source code and compiled upon.

Ms. Pac-Man (ミズ・パックマン, Mizu Pakkuman?) is an arcade video game from the Golden Age. It was produced by Illinois-based Midway Manufacturing corporation, the North American licensee of Pac-Man. Ms. Pac-Man was released in North America January 13, 1982, one year after the release of Pac-Man, and became one of the most popular video games of all time. This popularity lead to its adoption as an official title by Namco, the creator of Pac-Man. The game introduced a female protagonist, new maze designs, and several other improved gameplay changes over the original title. It became the most successful American-produced arcade game, selling 115,000 arcade cabinets.

Mutant League Football is a video game that was released in 1993 for the Sega Genesis. The game was designed using the Madden '93 engine, and features a different take on football, where the games resemble a war as much as a sporting competition. Electronic Arts ported the game to the PlayStation Portable as part of EA Replay. It was released in the United States on November 14, 2006. The PSP allowed a higher resolution for the game than seen on the Genesis, therefore bringing greater graphics to the game when played on a television screen via the new PSP Slim & Lite's output capabilities.

Mutant League Hockey is a hockey game that was released in 1994 for the Sega Genesis. This video game is a spin-off of Mutant League Football and features several of the same team names and players as well as new ones.

Mystic Defender is a two-dimensional action video game released for the Sega Genesis system. Originally titled Kujakuō 2: Geneijō (孔雀王2?) in Japan and based on the anime/manga Kujaku Ou, it is the sequel to SpellCaster for the Sega Master System.