Over the past quarter-century Pokémon has been one of the biggest franchises in all of pop culture, and it began as a trading card game in the mid-90s. Of course, there have been thousands upon thousands of cards produced throughout the years and some fans have been eager to collect as many as they can. But among those thousands are extremely rare cards, as sacred to Pokémon fans as certain elusive creatures are to Pokémon trainers themselves.

Many think of the iconic generation one Base Set as the rarest. However, some lesser-known cards are virtually unobtainable. Here's a look at the five cards that are considered the holy grail of Pokémon, so rare that very few exist and are worth a hefty price.

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Master's Key

Master's Key card art

The Master's Key was created more recently than most rare Pokémon cards out there. The card is more of a prize than a playable card, having been created for the 2010 Japan World Championship TCG tournament. The Master's Key was given to tournament finalists, and only 36 tournament participants were awarded a certified copy. Although its owner wouldn't be able to use the Master's Key to their advantage in a game, its rare status makes the card very valuable. In 2019, a copy of the Master's Key card sold for over $21,000.

20th Anniversary 24K Gold Pikachu

24K gold pikachu card art

Famous cards get more rare and expensive as they get older, and Pikachu's trading card is no different. Five years ago the Pokémon Company celebrated the TCG's 20th anniversary by reissuing the original Pikachu card. While the original is worthy of a re-release, the company decided to reissue it in 24 karat gold and presented it in an acrylic case. Famous Japanese gold maker Ginza Tanaka helped make this series of limited-edition Pikachu cards, and the amount of Pikachu in circulation is unknown. The card was only on sale for a brief period time in the Fall of 2016 and the price was over $2,000.

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Pikachu Illustrator

Pikachu Illustrator card art

The rarest items are usually the ones that aren't commercially available, and that was the case for the Japanese Illustrator Pikachu card. These were only given out to winners of a 1998 illustration contest and there were only 39 created. Pokémon fans who didn't have the skills to play the card game but could draw the characters had the chance to impress the company with their work. In 2016, a Pikachu Illustrator sold for over $50,000 from Heritage Auctions, but then in 2019 another one of the cards sold for $195,000.

1999 First Edition Holographic Charizard #4

Base Set Charizard illustration

While Pikachu is the most instantly recognizable Pokémon, Charizard is not too far behind. And the most famous Charizard trading card is the first edition holographic from 1999, as it has only 2,627 certified copies. The lucky player who draws this card will have plenty of firepower and a ton of energy against their opponent. The card's value has only grown in the two decades since its release and this year it sold at auction for over $100,000. Last year, the rapper Logic made headlines when he bought a Charizard card for $183,000.

No. 1 Trainer

No. 1 Trainer Pokemon card

The rarest Pokémon card in existence doesn't have Pikachu or Charizard on it, but just a silhouette of Mewtwo. However it is still worthy of being called the most desired Pokémon card in the world. Only seven copies of the Secret Super Battle No. 1 Trainer exist. They were created in the late 90s and had to be won in a regional event. The seven players who won this card got to participate in a secret tournament during the summer of 1999, a fascinating and mysterious event which adds to the lore of Pokémon trading cards. Last year, one of those cards for $90,000 at auction.

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