Red Costume

That's what I came here to find out. Was that outfit supposed to be introduced in the movie but then cancelled?

Haha and what's with robin pretending to be a grizzly bear to scare riddler?

I think it's more likely that the posters artist was colourblind. It is fairly common for colourblind people (like myself) to mix up pink and grey.
This is also evident with the uniform colours on Star Trek the animated series.

Same thing i came to ask too.

I don't think the designer was color blind, as someone would have had to approve it.

Is it an original image? Or did someone photoshop it? There are quite a few odd coloured pics around IMDb. But I can't see there being a red costume intended to actually use in the film. My only theory is it might be a real costume, however it was intended for photographing in black and white? Before films became color, quite a lot stars of black and white films had very odd color make up because it came out better on camera in black and white. A little Hollywood history you can read up on if you're interested?

I can't think of any other reason red wound be used?

Just part of the printing process of the time is what I assumed at first (high contrast to catch attention) but a few sources state that Bob Kane's original design was a red and black suit but it was changed, and this was a nod to that. But really, not 100% sure on that and think high contrast, limited # of colours certain prints makes sense to me.