Heritage Auctions in Dallas announced that a sealed version of Nintendo’s The Legend of Zelda from 1987 was purchased at auction for $870,000 on Friday, July 9.

The unopened, unusual copy had a price of $110,000 (£72,300) five days before the auction, according to Eurogamer.

Only an “NES TM” was considered more precious than this one, and there is only one unopened copy in existence, “and there is no telling whether or not that copy will ever come to market.” As a result, this cartridge had a grading—or wata rating—of 9 and is almost certainly the oldest unopened version one could practically hope to have.

“The Legend of Zelda marks the beginning of one of the most important sagas in gaming; its historical significance can’t be understated … it is a true collector’s piece”, Heritage’s video game specialist Valarie McLeckie said, as reported by AP News.

According to the auction house, it was an uncommon edition made during restricted manufacturing that lasted a few months in late 1987. The Legend of Zelda, initially launched in 1986, is a famous fantasy adventure game.

“Of all of the games we’ve offered in our auctions, this sealed, early production copy of the first game in the groundbreaking Legend of Zelda series is no doubt the apotheosis of rarity, cultural significance, and collection centerpieces. A proverbial trifecta of collector perfection that only one will receive the honor of calling their own”, auctioneer Heritage Auction stated.

“None of the copies we’ve offered of this title previously could even attempt to hold a candle to this one due to its incredibly rare variant that holds early production status,” the item description explains.

A sealed version of Nintendo’s Super Mario Bros. that was purchased in 1986 and left in a desk drawer was auctioned for $660,000 in April.

“Since the production window for this copy and others like it was so short, finding another copy from this same production run in similar condition would be akin to looking for single drop of water in an ocean,” Heritage’s video game specialist Valarie McLeckie claimed.

It was the best copy ever properly rated for auction, according to Heritage. It sold for far more than the $114,000 that another sealed version from 1987 sold for at a Heritage auction last year.