Quarth is a puzzle game where you control a shape that can be moved left or right as the screen scrolls down. Your goal is to fill in the gaps with blocks to create complete rectangles or squares, which will then disappear. New blocks will appear as the playing field moves down, keeping the gameplay exciting and fast-paced. If a line of blocks reaches the bottom, it's game over and you'll have 10 seconds to decide if you want to continue.
The gameplay involves clearing each level by filling in all the gaps, with each level consisting of 9 areas. Once you've cleared the last area, you progress to the next level. The game also features a Battle mode where two players can compete against each other.