You fly a futuristic fighter craft called the R-9a -Arrowhead- (at the 22nd century), named for its shape, and because it is the ninth model in the 'R' series of fighter craft. The mission is to blast off and strike the evil Bydo Empire. Basically it's one where you shoot everything that moves - some things shoot back at you while others just get in the way and result in your death on contact. The scrolling background is a sort of cavern with ceiling and floor outcroppings in places, and these, needless to say, can also be crashed into. Some of the sprites are pretty big such as a giant spinning wheel monster type waiting near the end of level one. You actually have to get your ship inside it and shoot it in the eye to close its account. And I'm sure there are a lot of even bigger ... alien-monsters waiting on further levels! Quick clicks on the fire-button produce standard bursts of laser fire, but should you require a bit more firepower then hold the button down for a sec. You can see the nose of the ship collecting surrounding atoms of some description - then when you release the button again, a large fireball zooms out.
This a pretty faithful conversion but although there are plenty of colors being used (in contrast to the CPC version), the MSX version suffers from the same issue as all of the other shooters for the system. The sprites move smoothly, but the background scrolling is incredibly choppy, which makes it hard to judge the speed of projectiles. It makes the game harder than it really is, and can potentially be quite frustrating! The sprites themselves move beautifully and some of them are really big! Graphically the best version is on the Commodore 64 though! Smoother and with by far better detail and colors at the backgrounds!
Sound is great on the MSX systems (especially when using the FM sound pack), featuring in-game tunes and excellent SFX. Note that the Commodore's version is superior (of course) due to its SID sound-chip, while the CPC version is bad (a few dull in-game SFX).