Evolva seemed to me a great game, at first. But it seems I was wrong.
Some years later, I finally bought the game, and then I played, it was not so interesting as it looked at first, but it wasn't a bad game, after all.
The graphics in evolva are old, just like the game, and if I remember correctly, they wasn't much in the time it was released either. The sound have few musics (or they are much alike, I really don't know). And the sound effects for the enemies are just what you are waiting for, some noises, and such, nothing much of innovation.
The mutation system is simple, anyway, you kill a enemy, and then you get what is left of him, if it is a new mutation, the blue meter on your screen will blink, and you will be able to get a new ability, if it is an old mutation, then you will only make your meter go up. The difficult part is to mantain your abilities at a good level, 'cause when one goes up, generally, other go down..
Well, the game isn't much, if you like the genre, you should give a check, otherwise, just get as far as you can.