The word "un-riddling" indicates the act of solving a riddle or puzzle, leaving one to wonder what the antonyms for this word might be. Antonyms for "un-riddling" might include the terms "confusing," "mystifying," or "baffling". If something is confusing, it cannot be easily understood, and may leave the reader or listener puzzled. Something that is mystifying may be difficult to understand, or have a sense of the supernatural attached to it. Lastly, something that is baffling may be confusing or unexplainable, leaving the person searching for answers feeling frustrated. In summary, while the antonyms for "un-riddling" may differ, they all seem to indicate a sense of difficulty or confusion.