Metal Slug[a] is a 1996 run and gun arcade video game originally developed by Nazca Corporation and released by SNK for the Neo Geo MVS.

Set in 2028, players assume the role of Peregrine Falcon Strike Force soldiers Marco Rossi and Tarma Roving on a fight against the Rebel Army led by Donald Morden and overthrow his coup d'état to prevent a New World Order.

Metal Slug was conceived by the same staff who created several titles at Irem that shared similar presentation such as In the Hunt and GunForce II, with the core concept during development being a simple but exciting side-scrolling shooter featuring a very easy control scheme and visuals inspired by the works of Hayao Miyazaki.

Metal Slug garnered positive reception upon its initial launch from players and critics, being lauded for its sense of humor, fluid hand-drawn animation and fast-paced two-player action.

Metal Slug is a run and gun game reminiscent of Contra where players assume the role of captain Marco Rossi and lieutenant Tarma Roving of the Peregrine Falcon Strike Force, shooting constantly at a continual stream of enemies in order to complete each mission.

Getting hit by enemy fire, colliding against solid stage obstacles or falling off-stage will result in losing a life and once all lives are lost, the game is over unless players insert more credits into the arcade machine to continue playing.

[1] Metal Slug was developed by most of the same team that previously worked on several projects at Irem like In the Hunt and GunForce II before departing from the company and forming Nazca Corporation.

[7][8][9] Shinichi "Hamachan" Hamada, Kenji "Andy" Andō, Atsushi Kurooka (currently of PlatinumGames), T. Yokota, H. Yamada and "Pierre" Takada worked as programmers.

[3][10][11] Artists Akio Oyabu,[12] Susumu, Kazuhiro "Max.D" Tanaka, Tomohiro, Takeshi Okui (currently of Monolith Soft) and Kozo were responsible for the pixel art.

[21][citation needed] The plot was similar to the final version but revolved around Regular Army members Phil Gene and Michiko Nakajima controlling the SV-001 and SV-002 prototype tanks instead.

[25] On July 5 the same year a Neo Geo CD version of the game was also released, featuring a "Combat School" mode that allowed players to revisit previously-played missions with new objectives.

[26][27] Though software market was being dominated by polygon-based games, Neo Geo conversions for Saturn and PlayStation were selling well in Japan, motivating SNK to produce ports of Metal Slug as well.

[28] To retain all animations frames of the arcade original, the Saturn version used newer compression techniques, inter-level loading and the 1 MB RAM expansion cartridge.

[53] GamePro's Major Mike agreed that the Neo Geo version suffers from low longevity, with too few levels and a complete lack of replay value, and also criticized the slowdown in the game, but Mike approved of the graphics, music, and arsenal of weapons, and summarized the game as "a soldier-slamming, side-scrolling, tour de force that dwarfs recent side-scrolling Neo shoot-em-ups, including the system's strongest platform offerings like Cyber-Lip and Top Hunter.

"[54] AllGame's Brett Alan Weiss and Kyle Knight praised its unique hand-drawn visual style, refined gameplay, simple controls, intense action, humor and replay value but criticized the game's slowdown when many objects are present on-screen, the overall length and found the music to be average.

[72] Several developers have also created games similar to Metal Slug such as Demon Front,[73] CT Special Forces,[74] Alien Hominid,[75] Commando: Steel Disaster,[76] Apocalypse Max: Better Dead Than Undead,[77] and Mercenary Kings.