A combination of old-school gameplay and arcade action make Metal Slug 3 worth at least a rental.
Like the other entries in the series, Metal Slug 3 is a fast paced, run-n-gun side scrolling action game similar to Konami's Contra series in some respects with it's old school “one shot and you're dead” skill based gameplay and hand drawn 2D visuals. The similarities end there, however. The series is known for its great tongue-in-cheek humor as you fighting off alien invaders, riding on camels equipped with cannons, and becoming morbidly obese from picking up snacks dropped from enemies. You can choose to play as four characters, though they only differ in appearance. Your default weapon is a handgun that has a decent rate of fire and no power at all. You'll commonly come across power-ups with limited ammo like heavy machine guns, flame throwers, enemy seeking rockets, and iron lizards – all with varying rates of fire and power behind them. In addition to firearms, you'll also carry the usual assortment of grenades for those extra touchy situations. While gunning through levels, you'll also come across vehicles equipped with Vulcan cannons and exploding shells. Vehicles vary from the original Metal Slug tank to the aforementioned camel and elephants, to robotic meshes, jet packs, and submarines. Speaking of variety, you'll find tons of variety in the games baddies. Sure, you have the cowardly soldiers from the enemy army here, but you'll also come up against giant crabs, aliens, giant locusts, zombies, and many more. There are also a variety of environments you'll be taken through like underwater levels, alien ships, jungles, icy caves, and vertical scrolling shooter levels.
Fans of the series won't find much difference between the Xbox version and its arcade counterpart. The visuals haven't improved (that's part of its charm anyways!) and the gameplay is the same, save for a couple of extras available after the arcade mode is completed. Since the game originated in the arcade, it's obviously not too long. SNK tried to get around this by limiting you to three continues and three lives per game (the lives can be adjusted to 5 from the options menu). The catch here is that when you're out of lives and continue, you're kicked back to the very beginning of the level instead of continuing where you left off (the heavy machine gun still drops from the sky, btw). This can make sense for the new internet high scoring feature available through Xbox Live, since the score won't continually rack up after you continue. However, as this halfway makes sense, it's also very frustrating since some levels are two parts and can throw large numbers of enemies and tanks all at once. If the smaller guys don't get you, you're guaranteed to lose a life or two lives on the large level bosses. So yes, the game can be nigh impossible, but it's a blast at the same time.
Unless you were raised in any era later than the NES era, you might scoff at the games visuals at first glance. The game keeps a very old school look going, and wasn't too visually impressive when it was originally released four years ago. If you look closer at it, you'll notice that the cartoony pixilated graphics are part of the game's charm, especially with the game's animations if you charge at enemy soldiers, they'll scream and run off, talk amongst each other, laugh when they kill you, only to run away when you come back and so on. You characters will also have some neat animations like when they turn fat, they'll start breathing heavy and fire fat bullets, or when they get turned into zombies they'll mindlessly walk along slowly with their arms out. Perhaps I'm trying to fit too much into this, so I'll just say that the animation is great and I'll end it there.
Sounds also handles itself well, as you'll get a good assortment of screams from your characters and enemies as they're getting shot down. The music is also good, but definitely takes a back seat to the action on screen and remains unobtrusive.
Metal Slug 3 is a fun old-school romp all while maintaining a dizzying amount of fast paced action which makes it a great twitch gameplay experience. The visuals may be a bit outdated and the difficulty levels may get to some, but you can't deny the game's charm which should be enough to warrant a weekend rental.