Combinable toy-set for forming pictorial compositions, that comprises a playing board and flat prismatic elements that can be placed on the playing board and fitted together, wherein the form of the elements can be triangular, square or rectangular or can take shapes defined by linear or circular boundary lines, in which the elements can be fitted in a square which has a side length equal to a basic size or in a rectangle corresponding to the half of the square or in a further square with side which is one and a half times as long as the basic size, or in case of triangular form at least one side of the triangle is equal to the basic size and the triangle is right-angled, isosceles or equilateral and the angles of any of the triangles are 30° or a multiple thereof, and in the medium portion of the playing board a pattern is provided which has a minimum size in any direction four times of the basic size and the pattern is composed of forms corresponding to the form of the elements, and the playing board comprises blank area around the pattern which is at least six times as wide as the basic size when measured at least in three directions. The presence of the pattern assists the player in creating compositions of certain complexity.