is an ancient pokemon card rare 10 Pokémon TCG: Roar Secret Rares You'll Want ASAP Pokemon Trading Card Game XY

Well not entirely all: No one is mistaking this card for Constructed Staple material

In super rare cases, a card is cut while folded, leaving a little bit of extra cardboard attached to the card (aka a flag)

steals it from a giant goose hydra

Even a 0.3 mm variance from these measurements raises flags during professional authentication

A well known fact, from the days before you had to play with sleeves, was also that the first printings of Mirage was far more glossy than other sets (same with some printings of Antiquities), which made Mirage lands sough after by semi-cheaters who wanted to be able to see if the top card of their library was a basic land