This book is a great way for you to spend a few hours in deep concentration, working out complex and fun puzzles and conundrums. (also known as "Rain Clouds", "Radar") is a variant of Battleship puzzle. The task is to mark certain cells of the rectangular grid as belonging to a cloud. The book comes complete with the solutions at the back, so you'll always know if you got it right, or can find the solution if you are really stuck for the answer.