Rocket Roger

You are Rocket Roger and on your way home to Earth, your ship has run out of fuel and you are forced to land on a mysterious planet. As you explore the planet you realize that scattered over the planet are fuel crystals and 99 are needed to refuel your ship. Problem is the locals aren't friendly and will try to kill you as you explore the surface and underground caverns. Some can be shot with your laser but others must be avoided and if you touch one then you lose one of five lives.