Question: Why did they have three different designs for Mr Freeze?
Question: What city was used for Gotham City?
Answer: There wasn't one singular city used. It was shot in and around various locations in California, plus on a lot of sets and backlots. Ex. Some scenes were shot in LA, some in Pasadena, some in Santa Barbara, etc.
Answer: There were three well-known actors who played Mr. Freeze, each one a different height, weight, and physique. As these were notable guest stars, the costume designers would adapt the costume to best fit each actor who likely would want to avoid comparisons to the other Mr. Freezes, incorporate their preferences, as well as refresh the look, rework whatever didn't work in previous versions, and so on.
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