Building one is definitely a puzzle. And trying to read it upside down/flipped without actually flipping it is also a kind of puzzle (i.e. like trying to run a compilation in your head, trying to see in your mind first before "running"/"compiling" the program).

They're also like the made-up language from the movie Arrival. You kind of need to know the end and the beginning at the same time.

I wonder how good GenAI is in generating ambigrams. I know they're very good in generating those visual illusions of having a face in a landscape. Perhaps that can be the next "Pelican test" once the Pelican test has been completely absorbed in training.