There are several materials used in making card sleeves
This is another way to identify a card, and can also clue you in to some special, often valuable cards: Secret rares have a collector number higher than the total # of cards (supposedly) printed in that set, for instance "65/64" or "110/105." If the collector number begins with "SH," the card is one type of "Shining Pokmon," with different art than the regular version
An autographed Alpha Black Lotus, Magic: The Gatherings legendary holy grail card, has set another new sales record for the trading card game after fetching $540,000 at auction
Some Vault cards may have a raised foil effect, like the Gilded Foil treatment from Streets of New Capenna
Its an opponent, not necessarily the one you just swung at, which makes it quite good