Metal Slug (Japanese: メタルスラッグ, Hepburn: Metaru Suraggu) is a Japanese video game series that includes different types of media. It was first created by Nazca Corporation before the company merged with SNK in 1996 after the first game in the series was completed. Other games based on the series include a third-person shooter to celebrate the 10th anniversary, several tower defense games, and a turn-based tactics game. The original games were designed for Neo-Geo arcade machines (MVS) and Neo-Geo home consoles (AES). Over time, these games were made available on other consoles and mobile devices. Later games in the series were created for different platforms. The games follow the Peregrine Falcon Squad, a group of soldiers who battle a rebel army, aliens, zombies, mummies, and other forces trying to take over the world. Since its debut, the series has gained a small but passionate fan base because of its unique artwork and humorous, exaggerated actions.
Gameplay
The gameplay includes run and gun elements, as well as shoot 'em-up mechanics in later versions. Run and gun gameplay involves players fighting many enemies while using powerful weapons that can be picked up. In most run and gun games, touching an enemy causes damage. However, in this series, touching an enemy allows the player to perform a close combat attack. The enemy may also attack if it has the ability to do so. The player's close combat attack is stronger than most regular shots. This allows the player to run toward enemies and use close combat to defeat multiple enemies at once. It also helps the player quickly defeat enemies that can take a lot of damage, such as the mummies in Metal Slug 2.
At the start of the game, the player has only a simple semi-automatic handgun. In Metal Slug 6 and 7, the starting weapon is a fully automatic handgun instead. As the game progresses, the player can find new weapons. Only one weapon can be used at a time. When a new weapon is found, it replaces the previous one. If the current weapon runs out of ammunition, the player reverts to the handgun, which has unlimited ammunition. Metal Slug 6 introduced a system allowing players to carry and switch between the handgun and two other weapons. Players also have grenades that can be thrown at enemies to cause more damage. However, grenades are limited and must be refilled using ammunition found during the game.
The main vehicle in the Metal Slug series is called the SV-001, or "Metal Slug." It is a small, cartoonish silver-gray tank with caterpillar treads. The tank has one cannon that fires powerful bombs in limited numbers and twin vulcan cannons that fire unlimited tracer bullets. The vehicle can jump and crouch. Crouching opens a hatch on the tank’s top, allowing the player to throw grenades already in their possession. Grenades are separate from the cannon’s ammunition system. The tank’s bombs can be refilled using ammunition boxes found during the game. The vehicle can run over infantry and perform a suicide attack, where the driver jumps away and the tank crashes into and explodes on the target. The vehicle can take three direct hits before being destroyed. A warning is given before the vehicle explodes. Enemy chaser variants have a shield that must be destroyed before the vehicle can be destroyed.
Over time, the vehicle’s design changed to include any vehicle with a vulcan cannon and a cannon suited for its role, as well as movement adapted to its environment. Some vehicles only provide vulcan cannons (which are more powerful than the handgun’s bullets and unlimited) but do not offer special bombs or armor protection. In Metal Slug 6 and the home version of Metal Slug X, the playable character Tarma can lock the vulcan cannons in one position and fire continuously.
Most Metal Slug games have six levels. Exceptions include Metal Slug 3 and 5, which have five levels, and Metal Slug 7, which has seven levels. In Western arcade and console versions, blood was censored and shown as sweat instead. However, a code exists in the Neo-Geo hardware’s BIOS to disable this censorship in both arcade and home versions.
Plot
The first game in the Metal Slug series follows the story of the Peregrine Falcon (PF) Squad, a small but skilled group of soldiers working for the Regular Army's special operations division. They fight against General Donald Morden's army to stop a military takeover and the creation of a new global system. Later games introduce characters from the Sparrows Unit, which is part of the Regular Army's intelligence division. Starting with Metal Slug 2, the PF Squad also battles an alien race called the Mars People, as well as other strange enemies like yetis, zombies, and giant crabs. These unusual elements were removed in the fifth game to return to the original story's style. The fifth game focuses on modern guerrilla warfare, keeping only a few quirky humor elements and paranormal enemies, except for the final boss. Metal Slug 6 brings back the story of the first three games, including Morden's Rebel Army and the Mars People. Metal Slug 7 features fewer unusual elements, replacing the Mars People with a futuristic version of Morden's Army.
In the first game, only Major Marco Rossi and Captain Tarma Roving were playable characters, with each assigned to one player. Starting with the second game, players could choose characters independently, and two new characters, Eri Kasamoto and Fiolina "Fio" Germi, joined the team. These four characters are often considered the most well-known group in the series. In the fourth game, Nadia Cassel and Trevor Spacey replaced Eri and Tarma. They did not return in later games because they were created by a different company, and the rights to the characters were kept by Playmore. Eri and Tarma returned in the fifth game. The Game Boy Advance version of the game added two new characters: PF Squad trainees Cadets Walter Ryan and Tyra Elson. Characters from other games, like Colonel Ralf Jones and Second Lieutenant Clark Still, appeared starting in Metal Slug 6. Leona Heidern, a teammate from King of Fighters, is available as a downloadable character in Metal Slug XX, a revised version of Metal Slug 7.
General Donald Morden is the main villain in the Metal Slug series. He is shown as a madman wearing a beret, an eyepatch, and a military uniform. In some games, he looks similar to Saddam Hussein. He appears in every game except Metal Slug 5. By the end of Metal Slug 6, he seems to change his ways, helping the player after being saved by the alien boss. His army, the Rebel Army, is the main enemy in most games, except for Metal Slug 5 and 6. In Metal Slug 4, he was linked to the Amadeus Terror Syndicate. In Metal Slug 7, he returns to his goal of taking over the world, this time with the help of the Rebel Army from the future. He becomes the final boss again, as he was in the original game. General Morden also appears in other SNK games as a guest character, especially in the SNK vs. Capcom: Card Fighters series.
Allen O'Neil, a sub-boss, appears in all games except Metal Slug 5 and 6. He returns in Metal Slug 7. He fights using an M60 machine gun, a knife, and grenades. Even though he is killed at the end of every battle, the game developers humorously bring him back in later versions. Allen's son, Allen Jr., appears in Metal Slug Advance as a drill sergeant for recruits but later reveals he is working for the Rebel Army. He can be fought as an optional boss in the final mission.
The Mars People are aliens in the Metal Slug series who want to take over Earth. They look like squids and move using their tentacles. They fight with gas and a laser pistol. In Metal Slug 2, they appear near the end of the game, with their mother ship as the final boss. In Metal Slug 3, they abduct Morden and a Regular Army member, only for the Regular Army and Morden's forces to attack their mother ship and defeat them and their leader, Rootmars. In Metal Slug 6, the Mars People, Morden, his Rebel Army, and the Ikari Warriors team up with the Regular Army to fight a new alien invader that feeds on the Mars People. In Metal Slug X, they appear as early enemies. The Mars People were the first characters from the Metal Slug series to appear in a fighting game, first as a hidden character in SNK vs. Capcom: SVC Chaos and later as an unlockable character in Neo Geo Battle Coliseum.
Development
The Metal Slug series was designed to be a simple, exciting side-scrolling shooting game with easy controls (one joystick and three buttons). The team that created Metal Slug for the Neo-Geo had previously made several games for Irem with similar graphics and gameplay, including GunForce (1991), In the Hunt (1993), and Gunforce 2 (1994).
Some sound effects and images from Irem and The King of Fighters games were reused in Metal Slug. The music was composed by Takushi Hiyamuta (credited as Hiya!), a member of the Nazca Corporation, which was bought by SNK in 1996. The first three Metal Slug games were developed by the Nazca team before SNK went bankrupt in October 2001, causing the original team to disband. To prepare for SNK’s collapse, the company Playmore was started in August 2001. It later became known as SNK Playmore in 2003, the year after Metal Slug 4 was released. After this, the series continued without the original staff, and Noise Factory took over development for games 4, 5, 6, and 7.