Can I get a list of LCS banned skins?

I don't think anyone really knows the full up to date list. Other than Underworld Twisted Fate(for his ghosty cards) and iBlitzcrank(for his laser pewpew grab) if iBlitzcrank is really banned, as well as Steel Legion Lux. I've heard people say Nunubot is banned(for some reason), but I see him from time to time in the LCS, LCK, LPL. I've also seen Dark Valkyrie Diana played recently in some of the Eastern Asia regions. And people keep saying that supposedly the "retired" skins are a no-no, even though I see them all the time as well, such as Vandal/Biker/Barfight Gragas, or Urfrider Corki. I likewise see World Championship skins brought out from time to time, such as SKT skins, Fnatic skins, TPA skins, SSW skins.

I say just let all the skins be usable. They're there to be played, not be trailer queens(for those who know anything about car shows).

I think I checked the LCS ruleset a while ago, and there was nothing on illegal skins in there.