It’s a rare game series that can defy changing tastes to remain popular yet unchanged across seven titles, but the Metal Slug series has achieved it. The timeless franchise feels as much at home in today’s retro-styled indie scene as it did in its era origin.
So let’s take a look at the Metal Slug series and how it has gunned down the competition.
Metal…Slug?!
The original Metal Slug was an indirect descendant of several games from development studio Irem, which had already found success with titles like R-Type, In the Hunt, and Gunforce.
Metal Slug was the child of the latter two, developed by ex-pats from Irem in the form of new studio Nazca Corporation. It combined the frantic shoot-em-up style of the team’s previous titles with the lessons learned in their development, creating a final product that was pure, distilled game design perfection. This gameplay was presented in a now-iconic, timeless aesthetic, making Metal Slug easily one of the most complete packages in gaming.
The bizarre name of the series derives (in a curious bond with the similarly-named Metal Gear series) from its mascot weapon of the same name, the Metal Slug tank. This was originally to be the main player-controlled entity before the game was overhauled to feature human characters. The Metal Slug still features as a vehicle in the original game and was later joined by a host of other player vehicles, also referred to as Slugs.
The original game was released on Neo Geo arcade software and its home consoles in 1996, but was also ported to various other platforms throughout the 90s.
Metal Slug’s graphical style and art design were so incredible that it still holds up today, as though it were an indie game merely styled as retro. The Metal Slug aesthetic is instantly recognisable with its chunky, bulbous look, even bringing organic curves and bulges to mechanised infantry. Some of its bosses and enemy machines are beautifully complex in their design, making them a joy to fight. It’s no surprise that the series has stuck close to that aesthetic across many iterations.
The original Metal Slug was a commercial and critical success and was followed by Metal Slug 2 in 1998 and Metal Slug 3 in 2000, though not before series originators Nazca merged with SNK. Among its other refinements and additions, Metal Slug 2 brought character transformations to the series. Characters could become a mummy or grow obese, dramatically changing how they are controlled. Metal Slug 2 was later remade as the definitive Metal Slug X, released the following year.
Metal Slug 3’s big contribution to the series was the introduction of branching paths, which added to the game’s replayability. For many, Metal Slug 3 represents the high watermark of the series, the perfect distillation of everything that makes Metal Slug great.
Feeling Sluggish
In the early 2000s, SNK found itself in a rocky financial position and eventually declared bankruptcy, forced to sell the rights to several in-house IPs, including the Metal Slug franchise. Developers Mega Enterprise and Noise Factory acquired the rights to Metal Slug and would go on to develop Metal Slug 4 as their first game in the franchise.
Metal Slug 4 didn’t take any huge chances, sticking closely to the formula established by the franchise originators. However, it added a scoring system that tracked the number of enemies killed in a given time span, while also including a new transformation and several new vehicles.
Metal Slug 4 received a mostly okay reception, and, for the most part, established that the new developers were capable of aping the success of the old. However, this would turn out to be the only game developed in the interim between SNK’s collapse and its rebirth as Playmore Corporation, later renamed SNK Playmore.
After re-acquiring the rights to Metal Slug, SNK Playmore returned to the developer’s seat for Metal Slug 6. Leaving the Neo Geo behind, this iteration was developed for the Sammy Atomiswave arcade platform and was ported to PlayStation 2 in the same year.
Metal Slug 6 followed up on the story of Metal Slug 3, with its rebels and Martians. Metal Slug 6 introduced two difficulty levels, with the easy mode giving players heavier firepower at the expense of an early end to the game. As usual, a bevvy of new vehicles showed up alongside old classics, and each character gained access to character-specific abilities. While it may not sound groundbreaking, this was the first Metal Slug to introduce weapon switching, allowing players to carry multiple weapons at once.
The Future is Now
The most recent entry in the Metal Slug series was released in 2008. Developed by SNK Playmore, Metal Slug 7 made its debut on the Nintendo DS, marking the first time the franchise appeared on a handheld console.
Taking advantage of the DS’s dual screens, Metal Slug 7 introduced a touchscreen level map, providing players with a helpful overview of their current stage. This addition made navigating the game world easier and offered more strategic insight than previous titles.
Later, a remade version of the game called Metal Slug XX was released for the PlayStation Portable and Xbox Live Arcade. This version refined and expanded upon the original, featuring branching paths that increased replayability—a nod to the changes introduced in Metal Slug 3.
While the main series hasn’t seen a new release since Metal Slug 7, there’s still plenty to discuss when it comes to the franchise’s spin-offs, compilations, and remakes. Although we won’t go into full detail, Metal Slug has spawned several handheld adaptations and mobile games, though the latter has had a mixed track record. All in all, the Metal Slug franchise has over 30 titles in total.
Despite the mainline series coming to a halt after Metal Slug 7, the game’s arcade-friendly, 2D shooter format remains an underrepresented genre in modern gaming. Unlike first-person shooters like Call of Duty or Battlefield, Metal Slug embraces over-the-top action, colourful explosions, and outlandish vehicles, somewhat echoed in more recent titles like Titanfall.
If you’re itching for a new Metal Slug, you may find its spirit living on in the indie scene, with games like Cuphead or Blazing Chrome serving as direct descendants. Additionally, retro collections continue to offer a chance to relive the classic titles from Metal Slug’s era.
While innovation hasn’t always been Metal Slug’s focus, the franchise still has plenty of firepower left. The Neo Geo brand, which Metal Slug was a flagship title for, has seen a resurgence with the Neo Geo X, and with SNK teasing the release of a Neo Geo 2, there’s hope that Metal Slug 8 might follow suit. It would be the perfect partner for a new console, offering a return to slick, stylized warfare after over a decade of quiet.
