A lot of fun
This is one smooth game. A tribute to the Raiden series, this flash knock-off is way too nice to be called a knock-off. A traditional vertical space-shooter, this game boasts smooth animation, having great graphics where it counts, while keeping your computer moving smoothly and quickly by keeping the backgrounds fairly simple, with a surprisingly artistic background thrown in from time to time. The game offers three selectable levels of difficulty, but even the easy level can be difficult if you're not so good at this type of game, the enemies darting around quickly as the screen rapidly becomes filled with enemies and their projectiles.
As far as gameplay is concerned, the challenge of the game rests in the player's ability to maneuver his ship to dodge enemy projectiles. Most of the boss enemies do the same old same old, shooting a bunch of stuff everywhere that you have to deftly fit in between. There are multiple levels of weapon upgrades, three primary weapons, each uniquely useful in different ways, two kinds of upgradable missiles, and a limited number of smart-bomb type weapons to keep you busy, as well as piles and piles of point items you can retrieve.
And there's more. You can save your game after each level if you'd like. When you win the game, it repeats again, somewhat harder, while you retain your score, adding to it as you go through the game again and again.
A small gripe: The game has annoying cut scenes after level 5 and after you beat the last enemy, and no way to skip them. They weren't cool the first time I saw them, and the next six times, they're even less cool.