Normal sudoku rules apply. Each digit 1-9 is depicted in this puzzle by a strange symbol. Deduce which symbol stands for which digit, and keep track using the key on the right.This grid contains numerous blob-like alien creatures, each consisting of two horizontally adjacent cells. Some blobs are shown; the others are invisible and must be located. Blobs do not overlap each other. Some blobs are clones of each other, ie: they contain the exact same two digits in the same order. A blob's left-hand digit always indicates exactly how many instances of that blob (including itself) exist in the grid. If there is a circular label in the centre of a blob, its symbol indicates the sum of the blob's two cells.