Columns

Columns is a single player, Falling block puzzle which describes itself as being based on Macintosh Columns by Chris Christensen which, this game claims, was itself based on XColumns by Jay Geertson.

The game consists of blocks which themselves consist of three coloured squares. All blocks are the same shape but the coloured squares they contain will vary. The player can position the blocks with the left/right keys, rotate the coloured squares within the block with the up key, and drop the block with the down key. The object is to align the colours so that three or more in a vertical, horizontal, or diagonal line are all of the same colour, when this happens they flash and disappear causing the squares above to drop down. The process repeats until either the player gets bored or the screen fills up.