Horizon Shift ’81 is a thrilling single-screen wave-based shooter with a real retro feel.
The player controls a ship in the center of the screen, enemies approach from above and below, and the player can switch up and down to deal with the oncoming horde.
Different enemies react differently to approaching the horizon: some sit on the horizon, others destroy sections of it, and others run up and down the horizon. The player has a “dash” attack, which allows them to knock enemies off the horizon and crash into other advancing enemies, earning bonus points for doing so. Knocking an enemy off the line fills up the dash meter, allowing the player to use a “dash chain” for more points.
The player can also jump (jumping upside down is a new and interesting challenge) and has a bomb that erases enemies from the screen and also restores the horizon.