Really loving the new clear blue with "aurora film" (got that term from a YJA auction translation) Marusan Pigmon. Anyone with this guy please post some better pics than mine.

You've got blue skies! Nice!
Aurora film...cool! Got mine and its translated as crystal.

Is there something inside or is the vinyl translucent? I'm not too familiar with this particular piece so I hope it's not a dumb question.

I think that's the "aurora film" or "crystal" mentioned above.
I am familiar with a similar substance commonly used to pack PC boards. Kinda like thick plastic wrap that is irridescent. Could this be some adaptation of that, fused to the inside of the figure?
Looks cool.

It is clear blue vinyl with that film stuffed inside. It is not fused to the vinyl. It is the same stuff in the Marusan Godzilla discussed in this thread but it is not tinsel http://www.skullbrain.org/bb/viewtopic.php?f=3&t=22744&hilit=marusan+godzilla Unfortunately it's not fully jammed into this toy like the Godzilla so the head is just clear. It's really neat stuff that seems to react differently when light is reflected off of it or passed through it.

m_t is that stuff you are talking about readily available? I would love to have some to shove into some clear vinyls. I'll have to ask around work to see if anyone has some lying around.

Hard to tell, but the film looks like mylar to me. Clear iridescent mylar shouldn't be hard to find.

I don't know how readily available it is, but I can prolly get you some at some point.

I used to buy that stuff and "alpha foil" at Tap Plastics. (Alpha foil is the opaque silvery laser-etched refractive stuff. Been around since the 1970s.) You can also buy iridescent transluscent mylar at many hobby shops. Sometimes you can find similar materials where gift wrapping is sold, but it's usually cut into ribbons or bows or pom-poms.