Played on the show by three actors, this one to me looks like the Otto Preminger Mr. Freeze, mostly because of the eyebrows. But they nailed it either way. If I remember my trivia correctly, the show popularized the character name, as there had only been a "Mr. Zero" in the Golden Age comics. I'm just freewheeling here, without looking it up, mind you.
The wind-up key on the backpack is a nice Lego touch! Since they were able to issue Mr. Freeze by himself, it makes me wonder about any other potential future releases. A Batgirl with her motorcycle would be a nice addition!