Karaoke Studio (カラオケスタジオ, Karaoke Sutajio) is a music video game designed for Nintendo's Family Computer. Physically the game acts as a subsystem designed to be inserted into the Family Computer cartridge slot. Several levels of the game can be played on the subsystem alone, and additionally, smaller expansion cartridges (originally available for separate purchase) providing additional levels and other new content can be plugged directly into the Karaoke Studio subsystem. The game comes with a microphone peripheral capable of detecting a human voice.

Karate Champ, known in Japan as Karate Dō (空手道, "The Way of the Empty Hand"?) is a 1984 arcade game developed by Technōs Japan for Data East.

Karnov (カルノフ, Karunofu?) is a 1987 platform arcade game. It is the debut of Data East's mascot of the same name. After Data East became defunct due to bankruptcy in 2003, Paon, a company comprising former Data East staff, acquired the rights to Karnov, along with multiple other Data East games. In the game, players take control of the title character Jinborov Karnovski (ジンボロフ・カルノフスキー?), or "Karnov" for short. Karnov is a strongman popularly illustrated as being from an unspecified part of the Soviet Union's Central Asian republic as shown on the original arcade flyer and again in Karnov's Revenge. As Data East's mascot, the title character was reintroduced in many other Data East games, including Bad Dudes Vs. DragonNinja in which he played a boss in the first level. Karnov later appeared in the 1994 Neo-Geo game Karnov's Revenge. This game, also known as Fighter's History Dynamite, is not a sequel to the original Karnov, but to Fighter's History, a competitive one-on-one fighter in which Karnov was the final boss.

Kart Fighter (Chinese: 瑪莉快打; pinyin: Mǎ lì kuài dǎ, lit. "Mario Fighter") is an unlicensed 2D fighting game produced for the Nintendo Famicom. The game features unauthorized appearances by Nintendo's mascot Mario and the rest of the cast of Super Mario Kart in a port of Street Fighter II. Since its release, Kart Fighter has received some media attention, including mostly positive reviews, in part because of its perceived similarity to the later Super Smash Bros. series.

Kick Master is a side-scrolling action video game for the Nintendo Entertainment System that was released in 1992 by Taito. The game has some role-playing game elements, such as leveling up.

Kickle Cubicle, known in Japan as Meikyūjima (迷宮島, lit. "Labyrinth Island" or "Maze Island"), is a puzzle game developed by Irem for the arcades in 1988 and then ported to Nintendo Entertainment System in 1990. Gameplay is somewhat similar to the Adventures of Lolo series as well as Pengo.

Kid Icarus (光神話 パルテナの鏡, Hikari Shinwa: Parutena no Kagami?, "Myth of Light: The Mirror of Palutena", lit. "Light Mythology: Palutena's Mirror") is an action platform video game for the Family Computer Disk System in Japan and the Nintendo Entertainment System in Europe and North America. The first entry in Nintendo's Kid Icarus series, it was published in Japan in December 1986, and in Europe and North America in February and July 1987, respectively. It was later re-released for the Game Boy Advance in Japan during 2004, and for the Wii's Virtual Console online service in 2007. A sequel to this game was released for the Game Boy in 1991, and a third entry to the series was published for the Nintendo 3DS handheld console in March 2012. The plot of Kid Icarus revolves around protagonist Pit's quest for three sacred treasures, which he must equip to rescue the Grecian fantasy world Angel Land and its ruler, the goddess Palutena. The player controls Pit through platform areas while fighting monsters and collecting items. Their objective is to reach the end of the levels, and to find and defeat boss monsters that guard the three treasures. The game was developed by Nintendo's Research and Development 1 division. It was designed by Toru Osawa and Yoshio Sakamoto, directed by Satoru Okada, and produced by Gunpei Yokoi. Despite its mixed critical reception, Kid Icarus is a cult classic and has shipped 1.76 million copies by late 2003[citation needed]. Reviewers praised the game for its music and its mixture of gameplay elements from different genres, but criticized its graphics and high difficulty level. It was included in several lists of the best games compiled by IGN and Nintendo Power. After the release of the Game Boy sequel Kid Icarus: Of Myths and Monsters in 1991, the game series lay dormant for 21 years. It was eventually revived with a 3D shooter for the Nintendo 3DS, titled Kid Icarus: Uprising, after Pit's inclusion as a playable character in Super Smash Bros. Brawl.