|Rail shooter, or more of a tunnel shooter, where you cruise down a long sinuous tube dodging obstacles or shooting forward at waves of enemies that swirl in along the tube walls from in front or behind. You can rotate around the tube (which rotates the tube in your view, so you're always at the "bottom") to get a better shot, or use an "Eraser" bomb that fires down the whole ring obliterating everything it touches--of course, you only have one or two of those. Quite Rez-like in its use of polygonal abstract forms for enemies and backgrounds, and the patterns rushing past on the twirling tube can get hypnotic to the point of making it difficult to concentrate--very pretty stuff indeed, but don't try playing it when tired because the trance music will lull you to sleep.|
You can play through the eight (I think) stages normally or in various "remix" versions but I'm not sure how they differ exactly. A boss sits in a big open space at the end of each level's tunnel and here you can move forward and back and rotate freely around the boss on the horizontal plane. The boss fights offer nice visuals and a sometimes surprising variety of attacks to counter.
And here comes the tricky part: you have eight or so weapons at your disposal at all times through which you can rotate with the shoulder buttons. Named after one of the eight Chinese astrological animals, ox, boar, rat, etc, each has a distinctive shot type and mastering the game requires learning which shot type to use against which enemy. I found it a bit of a chore to try flipping through the animals in the heat of combat--particularly against bosses, looking down to check your selected weapon will get you de-rezzed right quick. You can perhaps avoid this in part by configuring your own custom weapon order.
The flatshaded polygon graphics are downright amazing and really have to be experienced at full speed in order for their impact to be appreciated. The music complements the trippy graphics well but it isn't quite distinctive enough that you'll be rushing out to look for the soundtrack.
It's a good thing that the sound and graphics provide such distraction because the long tunnels between boss battles can get a bit monotonous, with the game sending one wave of enemy pellet ships swirling into your Rat cannon, then another, then another... zzz. I found that Bird got me through the first three stages (aside from the bosses) quite easily, as it launches a flock of auto-tracking pink projectiles that pretty much take everything out for you. In remix modes you can skip ahead to later stages (I got too sleepy to play stage four properly) and these look a bit more up-tempo, thankfully. IS won't set the world alight with original gameplay but it must be counted among the most stylish of techno shooters.