Forgotten Worlds, titled Lost Worlds in Japan, is a side-scrolling shoot-'em-up game by Capcom originally released as a coin-operated video game in 1988. It is notable for being the first title released by Capcom for their CP System arcade game hardware. The game took two years to develop, with a production budget of US$5 million.

Set in a distant future, an evil god known as Bios has destroyed most of the Earth, turning it into a desolated wasteland known as the Dust World. Two nameless supersoldiers are created by the people to defeat Bios and the eight evil gods who serve him.

Forgotten Worlds can be played by up to two players simultaneously. The player controls a flying muscle-bound soldier armed with a rifle with unlimited ammo. The Player 1 character is equipped with a long-range automatic rifle, while Player 2 has a short-range wide shot. The controls in the original coin-op version consists of an eight-way joystick for moving the character in the air while flying and a unique rotatable button known as the "roll switch". Rotating the switch left or right allows the player to adjust their character's aim in one of sixteen directions, while pressing it causes the player character to shoot his gun. This allows for the player to move their character anywhere while keeping their aim in one direction. Pressing the switch rapidly will cause the character to perform a "megacrush" attack which will destroy all on-screen enemies, but at the expense of a portion of their vitality gauge.