An old shareware Macintosh game, circa 1985-86. You are Cap'n Magneto, a little man with a cape, and your ship just crashed on an alien planet.
He begins the game unable to do much of anything. The first thing you must do is pick up his transponder. This device allows Cap'n Magneto to translate the language of the aliens. You run into several different types of aliens, who may be friendly and become your ally, or hostile and attempt to kill you.
Eventually you find useful items such as weapons, apples, and baubles. Most of these items are used to fight the aliens or bribe them to join your side. Near the end of the game you must kill or somehow sneak past the head alien and take his treasure. I was never able to pull it off.
(This was one of my first computer games. I used to play it on my father's Macintosh Plus. I haven't played it since, but I still remember Cap'n Magneto.)