That theory is correcthumidity changes cause expansion and contraction of the fibers that make up the cardboard side of the card, causing it to swell or shrink based on how much moisture is added or removed
As an eternal format, all cards are legal in Vintage decks, with some exceptions : cards with a gold or silver border, cards with an acorn security mark, and cards that appear on the Banned List are all prohibited
It can also be reused with cards like Academy Ruins restocking it to your library, recursion from your graveyard, bouncing and then recasting it, or flickering it back onto the battlefield for another round of exiling death triggers
Its also the only graded card Ive ever bought myself
She told Metro: "Its sometimes hard to know if youre selling for the right price, or if youre being ripped off with one you have your eye on