U235 is a puzzle board game. The game starts when Galactic Federation sends a secret agent to the planet Umhar. The aim is to neutralize the nuclear threat. To accomplish the mission the player must join together simultaneously two or more of the same elements indicated on the right side of the screen. The element moves in the indicated direction until it is stopped by another element or the edge of the board. The player may use many useful elements, such as mirrors (reflecting laser beam), bombs or detonators (destroying various barriers). However certain elements should not be brought into contact, for example the ball smashes the mirror and the bomb blows up if collides with the board edge.