Game program is comprised of a procedure for setting a block arrangement space 20 having a plurality of block locations 20a so as to correspond to each character, a procedure for instructing to insert a skill block 21 corresponding to a skill into said block arrangement location 20a, a procedure for computing and judging as to whether or not there is a collision between an instructed position of the skill block to be inserted and the skill block already inserted into the block arrangement space and for informing a player of the collision if any, and a procedure for displaying a state of arrangement of the skill blocks in the block arrangement space.