After years of scattered, piecemeal releases on various home consoles, SNK marks the 10th anniversary of the original Metal Slug by rolling up all seven Metal Slug arcade games into a single package with Metal Slug Anthology. It's a must-have for Metal Slug completists, if for nothing else, because it marks the first time that the relatively new Metal Slug 6 has appeared anywhere other than Sammy's Atomiswave arcade hardware. However, those same completists will likely be bothered by the unfortunate peppering of short-but-noticeable in-game load times found in all of the games. Still, the lovingly drawn 2D graphics look exceptional on the PSP screen, and the series' comically violent style and relentless action make for a singularly awesome experience.
At its core, Metal Slug is a traditional side-scrolling shooter. You run to the right, shooting and tossing grenades at swarms of enemies while dodging their bullets, picking up weapon upgrades, and rescuing POWs, with the action regularly punctuated by screen-filling boss fights. As generic as that might sound, Metal Slug has always separated itself from the pack with a goofy sense of humor, great-looking 2D graphics, and the kind of manic, sometimes punishing gameplay that leaves your hands aching. You'll also regularly happen upon the titular metal slugs--high-powered armored vehicles that come in a variety of forms. At their most basic, slugs look like superdeformed tanks, but they can appear as helicopters, jets, submarines, mobile suits, camels, donkeys, and more.
The games in this collection are mostly arcade perfect, right down to the bouts of slowdown you would have experienced in the coin-op version. The only thing that disrupts the mood are the extra loading screens that make the pauses between sequences linger for a little longer than they did originally. It's a minor point, one that will likely only irritate series veterans, but it does have a net effect on the pacing of Metal Slug. An inherent issue with taking the coin-op element out of arcade games is reconciling the fact that you don't need to drop quarters into the game to keep playing when you run out of lives. Limited continues can be too punishing for some, while unlimited continues can eliminate much of the challenge. Metal Slug Anthology sidesteps the issue by letting you choose between limited or unlimited continues. You can save your progress at any point in any of the games, a luxury that any arcade player would have killed for after having run out of quarters midway through a game. Metal Slug Anthology also features an optional autofire setting that lets you simply hold the fire button rather than constantly tap on it, which is a welcome addition for the aging (or simply lazy) Metal Slug fan.
Though the settings and the enemies you fight have gotten more bizarre as the Metal Slug series has progressed, the basic gameplay formula has remained mostly consistent. Still, there have been distinct highs and lows over the years. Metal Slug 3 is arguably the most ambitious, with a final battle that begins with a déjà vu fight against General Morden in his helicopter and ends with you fighting a gigantic alien mother brain in space, with several distinct sequences in between. Metal Slug 4, on the other hand, wasn't actually developed by SNK and almost feels like a Metal Slug bootleg. Metal Slug 5 was better and made the nearly inconsequential change of allowing your character to do a running slide, which was only useful for getting through low passages in a few specific areas. It was a change that disappeared in Metal Slug 6, though Metal Slug 6 has brought more changes to the series than the previous five sequels combined.
Things feel different right from the start in Metal Slug 6, as you're given the choice between an easy and a hard mode. The hard mode offers a standard Metal Slug experience, while in the easy mode your standard infinite-ammo pistol is replaced with an infinite-ammo version of the heavy machine gun. The easy mode also cuts the game short, ending before you get to the game's final level. While there have always been multiple characters to choose from in Metal Slug, they've always been functionally identical. Not only does Metal Slug 6 make Ralf and Clark from King of Fighters into playable characters, it gives each of the six total playable characters in the game some unique characteristics. For example, Marco's default weapon packs an extra punch, Tarma's slugs are tougher and more potent, and Eri gets more grenades. Additionally, characters can now carry two weapon power-ups at a time and can switch between them on the fly.
Metal Slug 6 is also the recipient of some audio-visual upgrades. The camera will automatically zoom out during specific encounters, a little trick that allows for even bigger boss fights. It also sounds significantly different from the previous Metal Slug games, with loads of new voice samples and new music that sounds much less synthesized. These are certainly technical improvements, but considering the inherent throwback nature of the series, these changes make Metal Slug 6 feel less authentic. However, all of the games included look great on the crisp PSP screen, which eliminates the blown-up, pixelated look that many arcade-to-home ports suffer from--the Wii version of Metal Slug Anthology included. Additionally, you can choose to play the game in its original resolution, an enlarged 4:3 aspect ratio that fills the screen vertically, or a stretched-out 16:9 aspect ratio that will fill the whole screen. While it's nice to be given the choice, the original resolution seems to be too small and the 16:9 aspect ratio too distorted, with the enlarged 4:3 aspect ratio providing a nice, happy medium.
Metal Slug Anthology is a great value. Along with seven full arcade games--each rife with alternate paths, hidden areas, and some clever Easter eggs--you get music, concept art galleries, and a confounding Q&A with developers of the series, where they discuss topics ranging from the underlying design ethic of the series to their personal casting choices for a nonexistent live-action Metal Slug movie. The Metal Slug series has been responsible for the best 2D shooter action anywhere in the past 10 years, and arguably ever, and it makes for a great fit on the PSP.