The game's DLC seem to have been blocked in Brazilian Steam store.
That's what I see: http://store.steampowered.com/app/57400/?cc=br and that's the US store: http://store.steampowered.com/app/57400/?cc=us
Even though the Nightwing DLC is visible, it says I need to have the base game (and of course I do have) to be able to buy it.

Any statement on why did the DLC get blocked months after being released?