Just like Konami's contra, all you need is the one cheat code and another player to bring back this game's allure.
Don't waste your time trying to beat this game without a cheat code-- it's that difficult.
Just hit "Up, Up, Down, Down, Left, Right, Left, Right, B, A, Select, Start " at the startup screen and you'll have enough lives to enjoy this game.
Classification:
I would classify this game as a nostalgic classic, one that's sure to satisfy you and a friend. It's decent in one-player mode, but just like contra, why play with one when you can double your offensive power.
Originality:
This game seems to take place inside a body and in space --at the same time. The "bad guys" look like cells, brains, bronchial tubes, more body parts, etc.
It's one of those yell-at-the-screen, blame player 2 for being a moron games; and coming from the NES era, it's truly a gem.
Learning Curve:
Like contra, you play through it not knowing what all the weapons/ add ons are at first, but you pretty much get used to everything by level one.
Time Spent Playing, to date:
This might as well be my favorite NES game, EVER. I bring this game out to play at least twice a year. It comes from the console that started it all.