The Batman: Arkham City preorder plan is so complicated, with various offers from retailers all over the place enabling different costumes and content, it seems like you need to be the World's Greatest Detective just to figure it all out.And here's another clue to the mystery: That Batman Beyond skin seen so long ago is now being offered as a reward from energy drink NOS.
To get it, all you have to do is chug a NOS (or just buy it and pour it out, we won't judge), grab a code from the can and plug it in on the website, and then redeem the point you earn for the skin. According to the NOS rewards page, you can use the skin after you complete the game's main story, or in any of the challenge maps. Was Terry McGinnis always this buff?
NOS also notes that this reward is offering "early access" to the skin, so if you can't buy NOS where you happen to be, this (and the other bonus skins) will be available later through normal DLC channels.