To the random observer this would just seem to be another random top down shooter but raptor has it where it counts. The difficulty curve is just right as there is 4 areas in the game and each area is broken down into waves (levels) each one ending in a boss, some having multiple bosses. There is also difficulty levels ranging from the easy rookie mode to the hard as nails elite mode to provide plenty of challange. Also as far as i remember the save function in raptor was also unique for its time so you can just carry on where you left off which is just as well as the game is actually fairly long.
The actual gameplay is pretty self explanitory as you fly your eurofighter / f-14 mashup across the map eventually reaching a boss or a base to destroy. Sounds simple but you can guarentee that the enemy wont make it that easy, especially on elite
Another nice feature is the ability to upgrade your jet with new weapons, usually in a top down shooter you would expect you just pick up weapons as you go along which is half true as there are some weapon pickups in some levels but for the most part you buy your weapons from "Harold's Death Emporium" between levels with your money earned from destroying stuff.
The graphics are quite refreshing, just look at the screenies and its fantastic especially since this was from the DOS era with some nice attention to detail like they bothered to put in a image of the plane banking when you go left or right, you can move quite freely around the screen and you'll need that especially on the harder difficulties to avoid all the projectiles. There also includes atleast 2 night levels and if you are bored with the enemy set (which is very varied and each with their own unique way of attack) there is even a cheat to replace all the enemies with farmyard animals (although i havnt tried it yet)
In Short i think good gameplay, replayability and its good on the eyes too so i'd reccomend this even if shooters arn't quite your thing, you might still be surprised