Grime Z80 is a remake of the 1984 text mode game Grime for the IBM PC, now ported to an assortment of 8-bit computers and devices all based on the Zilog Z80 CPU. Like the unsanitary original, it inhabits the general territory of Centipede crossed with Conway's Game of Life: a multi-directional shooter where you battle an expansion of sloppy ooze which behaves and grows like a cellular automaton.
The little battleship roams the fixed playfield with its infinite supply of grime-destroying bullets, which can be shot in four directions (the game generously does the shooting for you: in the original game auto-fire was optional -- here it isn't). Mobile enemies travel across the screen and seed new patches of gooey mold; as the muck spreads and mutates, it spawns slimy seepage that actively seeks you out. You get three lives, which you lose if your ship touches one of the moving spores, or gets completely surrounded by goop.