/Begin Edit Ignore me I got confused. :D I see what you did. I'll leave the below so that others might see my confusion. I was confused by your emphasis of "ee

/Begin Edit Ignore me I got confused. :D I see what you did. I'll leave the below so that others might see my confusion. I was confused by your emphasis of "eel in the corner" because there are valid combinations that lack that. /End Edit The issue is that all combinations are valid given the conditions. >You can paint a single sea creature of your choice on each of these canvases, with one condition. I would like to see a picture of an eel when I move my gaze vertically or horizontally. So there must be at least one eel in the vertical column and at least one in the horizontal row. "At least one" means there can be multiple - and, in fact, without having an eel in the corner it is necessary to have at least 2 eels. So "a single" simply means a painting cannot be of an eel and a sea turtle. Given X = No eel and O = Eel X O X XXO The above is a valid combination. As is the below: O O O XOO Now if you consider: O O O OOO All combinations will result with an eel in the corner and all combinations are equally valid. All paintings are of a single sea creature (an eel) and meet the requirement of vertical and horizontal inclusion.