What additional challenge maps are available for Batman:Arkham Asylum?

Question

I loved Batman:Arkham Asylum and am wondering what are the additional challenge maps available for it? I can't seem to find an authoritative list anywhere. The challenge maps I have seen appear to be duplicates of ones I've already played, just in different settings. What is different/unique about each map, i.e., why would I want to play each one?

Answer 1

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You can find a list of DLC for the Xbox360 here
You can find a list of DLC for the PS3 here

From Wikipedia

The Insane Night map pack was released on September 17, 2009 for PlayStation 3 and Xbox 360 and features the Totally Insane "FreeFlow" combat map and the Nocturnal Hunter "Predator" map.

The second free pack, Prey In The Darkness, was released on September 23, 2009 for PlayStation 3 in the North America, and both consoles in the EU.

The Collector's Edition included an exclusive preorder challenge map from GameStop was announced called Dem Bones. It places Batman under the influence of Scarecrow's 'fear toxin' causing him to hallucinate and all the enemies to be seen as skeletons.