Battlantis

To start playing, press Enter to begin a new game. You control Cripeuss III at the bottom of the screen, moving left and right with the Arrow Keys. Your goal is to shoot the descending monsters that march down the playfield in formation. Press X to fire your standard shot upward.

The core loop is simple: survive wave after wave of enemies by shooting them before they reach the bottom. Some monsters will break formation and charge straight down at you, so be ready to dodge. Occasionally, two monsters carrying an ark float across the screen; shooting the ark drops a temporary power-up that gives you a more powerful shot for a short time. If an enemy reaches the bottom row, it will fly sideways toward your position, adding pressure to keep the screen clear.

There is no continue or save feature - typical for arcade games of this era. Each credit gives you a set number of lives, and the game ends when all are lost. No special menu navigation is required; the game boots directly into attract mode and starts with a button press.