Atari 2600- Swordquest (Wikipedia)
Swordquest is a series of video games originally produced by Atari, Inc. in the 1980s as part of a contest, consisting of three finished games, Earthworld, Fireworld and Waterworld (with these titles occasionally appearing on cartridge labels and boxes with capitalized central Ws, e.g. EarthWorld), and a planned fourth game, Airworld.