The other day I wanted to say to my students
That was easy, here's a trickier one.
Ça c'était facile, en voici un plus délicat.
But I think délicat is of higher register than tricky. Dictionaries give as translations of tricky, depending on the context, rusé, difficile, among other words. I am wondering if there are other words or expressions that better convey the idea of tricky as given, for example, here
(1) If you describe a task or problem as tricky, you mean that it is difficult to do or deal with.