Tennix is a game where you will be able to play tennis against the computer.
And, if you want to play against another human, you can also do this.
It is possible to choose between four different international courts, each one with its own surface, weather and time of the day. Sometimes you will play in the night, sometimes in the day. For some strange reason, anyway, you will not be able to see the playing field clearly. The only visible zones will be those two illuminated by the focus. During the day it is the same, only the background colors will change. You can control the player with two combinations of keys, or the mouse. You will be able to go up, down (no right or left), and hit the ball in two ways: the common hit, and an aerial hit. It is very difficult to play this game, as you have to press a key (or the button of the mouse) to apply strength to your shot, but as you have to hit the ball with a small portion of your racket, it is very difficult to make a good shot.
As the score is shown in the darkest zone of the screen, you will not be able to see it clearly.
In brief, this game is hard to play, and has very few options. I don´t recommend it at all.