You are the Wizard and your opponent is the Dragon. You can use the up arrow key to move the wizard up by 10y and you can use the down arrow key to make the wizard move down by 10y. If you press the space key the wizard will shoot lightning at the the dragon. If you miss the dragon will get a point but if you hit the dragon you get a point. The dragon can shoot fire and if the fire hits you the dragon gets a point and if it misses nothing happens.
I ensured that you always get a point and there is no glitch in which the lightining bolt hits the dragon and the dragon gets a point. I also ensured that if the fire hits the wizard the dragon gets a point. If you drag either charecter there might be a glitch.