Heptrix takes place on a grid that is 14 blocks long and 24 blocks high. Pieces of various configurations (each made up of 7 blocks) fall one at a time from the top of the screen. The player must manipulate the pieces as they fall to fill in horizontal rows (similar to Tetris). Each piece landed scores 7 points. When a row is full, it clears, giving the player 70 points. If multiple rows are cleared at once, the score increases exponentially. After 7 rows are cleared, the game progresses to the next level. The speed at which the pieces fall increases with each level. The game ends when the pieces reach the top of the screen.