"Does a dragon live under the park?"
Translation:공원 아래에 용이 살아요?
I always thought -이까 is for asking questions in Korean; just like ですか (desu ka) is in Japanese.
That's just one of the many ways to ask a question: -니까 is the question equivalent of -니다 in formal speech.
For the -요 form here questions don't change the ending as compared to their statement equivalent.