In Batman: Arkham City for the PS3 and Xbox 360, you can play as Robin on the Challenge Map stages.
First, you have to have the Robin Bundle Pack which is available via download. If you pre-ordered the game, it may have come with a code that you can enter to download it for free.
Once the Robin Bundle Pack is downloaded and installed, you’ll be able to select Robin on the Challenge Map stages. Robin has his own set of moves and gadgets as well.