An evil alien menace is threatening to invade Earth. You, a slow, flimsy ship constructed out of aluminum foil and prayers, must kill enemies firing endless amounts of bullets and steal their batteries, which somehow are compatible with your ship.
Aliens are threatening to destroy Earth and... well, really, that's all you need to know. But you didn't come to a Cracked topics page for a bare-bones explanation of the plot.
The main villain in the original Gradius trilogy is a gigantic evil brain known as Bacterion, and the last hope of humanity is the combined military forces of all the sovereign nations in the world fighting side-by-side with several fleets of dreadnought-class spaceships and... yeah, right. Instead they trust the fate of our race to a flimsy, slow spacecraft that explodes whenever another enemy so much as sneezes on it.
Fortunately, the Vic Viper (your ship) comes with a wide array of custom weaponry and shield technology, as well as acceleration boosters and auxiliary turrets called "options". But you don't get to start out with any of that stuff because god damnit those batteries are expensive!
Konami: Sponsoring military clusterfucks since 2633.
So in each game, you fly through multiple obstacles to reach the aliens' mechanical base (which appears basically the same in every installment) and destroy the brains. Once you get to the brains, there's really nothing keeping you from destroying them. And really, would you have expected for the enemy ship to be able to reach you anyway if you were surrounded by all those fleets and weaponry?
Mother Brain, eat your heart out. Or whatever the hell it is that keeps you alive.
Every game reveals that these brains (particularly the final boss Gofer from Gradius II) are a part of Bacterion, which is apparently some sort of super-sentience. This is the enemy fought in Gradius III, originally the last of the trilogy.
And no, obviously you can't just nuke the enemies. Why? I don't know, I guess now the world is enjoying a utopian state of peace where they've eliminated all nuclear weapons or something. Never mind that at the end of the third installment, it's revealed that Bacterion was born out of the greediness of mankind. Though I guess that explains why the batteries that enemies drop are compatible with the Vic Viper; still, couldn't they have used a different kind of battery? After all, Bacterion had three games' warning that the Vic Viper was coming, and would probably have at least felt when Gofer was destroyed.
You'd really think a giant brain would have better foresight.
Cracked has already mentioned that the Konami code was created because the play tester couldn't play the game, but what they didn't tell you was that the home ports were actually somewhat watered down from the original arcade versions. These arcade games were never released in the States, because the Japanese thought they would be too difficult for American gamers.
I, for one, find their lack of faith disturbing.
Like any long-running game series, Gradius has developed a number of trademark enemies and themes throughout its career. Here are some of the more recurrent ones:
No options and no shield? You're fucked, sweetheart.
These are active bloody volcanoes that erupt slowly but steadily, spewing chunks of rock into the air. (Or in the NES version above, they erupt at a constant speed because that's all the system could render.) And no, you can't just fly through this part; you have to stay and fend all the chunks of rock off. I don't know why you even bothered to ask.
Also, they like to throw these mini volcano robots in from time to time. Just... smile and nod.
My guess is the volcanic ash is messing with the pilot's head.
Not the physical act of dying in a Gradius game, mind you (though the game is well known for that, too). I'm talking about this guy:
Not pictured: Missiles, bullets, and an open core you have to shoot like crazy.
This thing was the end-of-area boss for stages 1-5 in the original Gradius, and has since made appearances with a giant laser cannon. Oddly enough, fighting Death is one of the less difficult parts of playing Gradius.
From Gradius II onward, boss rush battles became commonplace. Here are some of the more common enemy ships you would have to fight in these rushes:
Not pictured: the dignity of the Gradius franchise
Yeah, I think we get it by now, Konami. You created Gradius, and want us to hate you as much as possible for it.
The MOTHER FUCKING MOAI STATUES!!!!
If you gave acid to a traumatized Vietnam vet, and then made him have a Rambo-style flashback, he would probably tell you nightmares about his fight with the evil Moai statues and their dreaded laser-Cheerios, and you would dismiss him as crazy. Unless you've played any Gradius game, in which case you yourself will go through a similar flashback and beg for some kind of awakening. I don't know what happened to the Moai people, but they deserved to die a horrible, brutal death for this.
Not pictured: any trace amounts of sanity or hope for the general state of the universe.
Gradius is widely considered the grandfather of the side-scrolling shooter genre, having spawned several sequels as well as spinoffs and other franchises like LifeForce, R-Type, and Touhou. In the 25-odd years since its release, it has remained popular in the eyes of retro gamers and masochists (one can assume mostly the latter). Another significant factor behind its success is the fact that the music is just plain awesome.