Batman Adventures: Riddle Me This!

When is a Riddle not a Riddler?
Riddle me this, Robin!
Who sings for Nightwing?
Friend or foe? 

The Riddler. He’s a constant thorn in Batman and Robin’s side who always teases the Caped Crusader and Boy Wonder with enigmas and questions pertaining to his master plan, but is the Riddler truly a villain or a hero? Can the king of conundrums turn over a new leaf to become a master detective and crime-fighter himself?