I love shooters, and I remember playing Raiden Trad on the Genesis all the time with my dad. However, when my family moved to Virginia we sold the Genesis we had, and I had no shooters for a while, other than River Raid. Then, my parents bought a huge lot of G-cube games, with Chaos Field included, and I was pumped. Chaos Field didn't dissapoint.
The game falls into the "bullet-hell" sub-genre of shooters, covering the screen with projectiles that you must either weave in-between or wipe out with your sword. The game starts out easy, but soon builds up. The later levels are fast and difficult; to this day I have yet to beat the game.
To help you out, you get several special moves: the Wing-layer, which act like a shield and does damage if it touches the enemy, the Lock-On, which lets you shoot at the enemy's weak spots directly, and finally, the Chaos Field. In the Chaos Field, you can do more damage, and your special moves become more potent. The enemy becomes far more difficult. You can switch between the Chaos Field and the Order (normal) Field when the wings of your ship are "glowing". Since switching between the fields will give you a few seconds of invincibility, and eliminate all the bullets onscreen, you'll find yourself jumping between the fields when you're in a tight spot.
As the VGC pointed out, you fight nothing but bosses. I personally loved this. I find it thrilling, figuring out the patterns, narrowly threading the needle between shots, and watching the awesome explosions when the bosses go down. And I should note that if you play the Original mode, rather than Arcade, you will fight minor enemies before the big ships.
In each stage, you face three ships, with the third one being the boss. There are five "Phases", totaling 15 big ships to take down. You have 3 different ships to choose from for this task, and they're the usual suspects. You have a fast ship with weaker firepower, a slow ship with strong firepower, and one thats in-between. Each of them has typical weaponry, too; laser weapons, rapid-fire, and "burst" type.
The graphics in this game are good, with HUGE enemies that when defeated, create a screen-shaking explosion. The ships that you can pick from are wicked, with short bodies and wide, pointed wings. They remind me of F-117's. The music is awesome, with a variety of pulsating beats that pump up your adrenaline. I reccomend buying the soundtrack. The gameplay is love-it or hate-it, but should appeal to fans of Maniac shooters
The game is a lot of fun, but some shooter fans may not care for the non-stop bosses, and if you don't care for shooters in general, you certinately won't like it. I give it a B, and you can get it for around $20-30. If you aren't sure, rent it first.