On the sushi menu of your favorite Japanese restaurant, you know unagi as a savory, slightly sweet freshwater eel that's better tasted than ogled. So it's the same in Ninjadoodle's hors d'oeuvre portion of sixteen puzzles, Unagi 16.
Gameplay in this case is like the "find the code and enter it below" puzzles in Ninjadoodle's Binga series. If you can point, if you can click, you are well on your way. In each level, manipulate the images in the clues given until you can decipher the code by calculating, doing some computing, and applying a bit of logic. At times you'll need a good memory or a notepad and pencil nearby, occasionally you'll have to do some dexterous clicking and, in the end, there's a little arcade-like challenge to sum it all up. There's not much else to it but it's strangely compelling and oodles of fun.