You are in control of a squad of tanks, who are out on patrol to destroy enemy vehicles. You use a radar to track enemy tanks, a sight to target them, and you shoot at them. If they fire back, you can shoot down their projectiles. Instead of having an obstacle course like another game, it has many changing variatons. You not only have to deal with a day/night cycle, but you also have varying weather to work through, like fog, snow, rain and others. If a tank hits you, you don't always die at once. Sometimes part of tank is damaged, such as your radar jamming, your visuals going out (you're pretty much blinded for the most part) and so on. After you destroy a squad of 12 tanks, you're off the next area.
The graphics are pretty good. The ground gives you the illusion that it's scrolling by as you move along, the tank's movement is smooth, and when you're dusted, a static effect is seen -- it's just excellent. The only sounds are you tank's motor, gun fire, and of your indicators beeping (indicating damage). Once you take damage, there's no way to repair it, so you're pretty much stuck with a blinking screen if you get hit.
Robot Tank is very good, even surpassing the 2600 version of Battlezone. If you were disappointed by that port, park you tank here for a round or two.