* "Thousands" is vague: Are you talking about cards worth thousands of dollars, or simply a collection of thousands of cards?
* Fakes are common: Sadly, fake Pokemon cards are a real problem, especially for valuable or rare cards.
* It's hard to tell: Some fakes are very convincing, even for experienced collectors.
To determine if your cards are fake, you should:
* Research: Look up specific cards online to compare to yours. Pay attention to card texture, artwork, and any specific markings.
* Consult experts: If you have valuable cards, consider getting them authenticated by a reputable service.
* Be cautious: If you are buying cards online or from unknown sellers, be very careful.
Remember:
* It's better to be safe than sorry. If you have any doubt, don't assume a card is real.
* There are resources available online and in your community to help you learn more about authenticating Pokemon cards.