Hoverdia Eighteen is first of its kind and a brand new Two-In-One number puzzle. The main puzzle is best represented by 8 long horizontal blocks and 8 long vertical blocks, with each long horizontal block and each long vertical block consists of 8 small boxes, which give the total of 64 boxes. Each long horizontal or long vertical block which consists of 8 boxes must contain one of the numbers from 1 to 8 inclusively without repeating any thereof - This is Rule One. The main puzzle with 64 boxes is also alternatively represented by 4 sub-quarters which are called Quarters and each quarter is made up of 4x4 short blocks. For Rule Two in any of the 4 quarters, after having complied with Rule One, each block, consists of 4 boxes, must be added up to the sum of 18 horizontally, vertically and diagonally.