KNOXVILLE, Tenn. (WATE) — A sealed copy of the 1988 video game Super Mario Bros. 2 sold for $88,550 during a recent estate sale after the death of a Floyds Knobs, Indiana resident.

The pristine cartridge was found inside a box of Nintendo games in the back of a crowded walk-in closet in Patricia Martin’s home, according to auction house Harritt Group Inc.

“At first glance, it was a comforting wave of classic Nintendo nostalgia. All the classics were there, Super Mario Brothers, Duck Hunt, Qix and even an NES console. So we did what any children of the 1990s would do: we fired up the console and tested the open games. It was a great day!” the Harritt Group wrote in the description of the item. “At a second glance, it was something else entirely. The seemingly ordinary collection included an extraordinary unopened copy of Super Mario Bros. 2.”

The unopened copy of the popular game received a near-mint condition rating of 9.8 A+.

The rare collectible was sold during a two-week auction by Harritt Group Inc. to a Florida businessman. The money will be split between family members of Martin, who is a native of Lenoir City, Tennessee.

Collectibles such as trading cards, comic books, ticket stubs and video games have become popular among financial investors seeking to turn a profit on hard-to-find items with cultural significance. A 9.8-rated copy of Super Mario 64 set the record for the most expensive sale ever of a video game at auction earlier this year, fetching a whopping $1.5 million.

In September, a 9.6-rated copy of Spiderman’s first-ever comic book appearance set the record for the most expensive comic book ever sold. The 1962 comic Amazing Fantasy No. 15 was sold at Heritage Auctions for $3.6 million.

The collectibles craze has created aggressive and sometimes even dangerous conditions for collectors and investors alike.

After a high-profile assault over sports trading cards at a Wisconsin Target store in May, the national retailer chose to pull Pokemon and sports trading cards off store shelves nationwide due to safety concerns for both customers and staff members.

More than $50,000 worth of sealed sports trading card boxes were stolen from a Knoxville collectibles store in May when a thief broke in and made off with some of the most in-demand products. A few days earlier, an estimated $25,000 in sports cards was stolen from a memorabilia store in Lexington, Kentucky.