If the color is consistant on the figure its probably not a sun fade, but I'd just chalk it up to production variations.
A variant figure, to me, suggests that the visual difference of the figure is the result of an intentional production decision to modify the color of the paint or plastic of a figure for a significant portion of the production run, meaning they may be rarer but there are still a lot of them and they are consistently colored. Varying hues like this are not uncommon, even though this is a drastic example, but most likely they are due to unintentional variations in paint mixing across factories and runs during production.
Also just wanted to make a note since I keep seeing mentions of what kind of light was used to take a photo...this alone ultimately doesn't really tell us anything. White balance and color saturation are controlled by the camera. A "room light" could be incandescent, fluorescent, halogen, etc., if you dont provide the temperature of the light its null. If you use "auto" white balance in addition to ommiting the light temp, then there's not a lot of certainty remaining at all. Even photos taken in "natural sunlight" can be incorrectly balanced. Not to say anything about this particular photo btw, it seems fine, just something to consider for other situations.
Edited by bachamn, 19 February 2015 - 11:00 PM.