Help the brave caveman to escape of the anachronistic elephants and get safely to the place where the food is abundant. Your only weapon is the stonezooka (nothing else has been invented until now). Some bonues that you'll find on the way will help you to give more power to the shot, extra lifes or temporary invencibility.
Move the mouse to aim the stonezooka, click to shoot. Use the A/D keys to go back and advance, respectively, and the space bar to jump.