Say, are any part of the skin going to be pale and flaky, like real moulting skin?
I suppose someone else mentioned blood, so it all depends on what kind of transformation you have in mind. Chaos figures don't seem to be ones to go for a painless process when there's a painful equivalent, so I wouldn't blame you for going with the blood option. But I bet a snake-like skin-shed is something almost no-one's tried.