Ludus

This game is less of a game and more of a puzzle, which explains why there's such an odd number of players possible. There's a four-piece modular board that forms a large room with walls spread around the board. There are also color-coded targets on boards. Placed on top of the surface are four robots. The idea for each turn/puzzle is to get the like-colored robot to randomly selected target. The trick is that once a robot starts moving, it will continue to move until a wall or another robot stops it. Therefore, players are seeking a sequence of moves for the robots which will enable them to move the required robot to the target in the fewest moves.

There are two versions of this game: Ricochet Robot (the original, in a maroon-ish box), and the reprint Ricochet Robots (in a blue box). Gameplay is identical in both cases, but the Robots version has slightly more involved maps, with reflectors that will affect some colors of robots but not others. The components from the two versions can be mixed and matched to produce many new boards.