1. An extremely rare early prototype of Nintendo’s Mike Tyson’s Punch-Out!! has emerged, featuring unique differences from the retail version, including game content and cartridge makeup.
2. The prototype employs stamped mask ROMs, unlike typical prototypes that use rewritable EPROM chips, raising questions about its purpose and authenticity.
3. There are notable gameplay differences, such as arcade fighters appearing in the intro and the presence of two mysterious, unreleased fighters, Rockyhead and Mongol Khan.
Rare Find of Nintendo’s 1987 Prototype
An incredibly rare early version of Nintendo’s famous Mike Tyson’s Punch-Out!! from 1987 just surfaced on the internet, and it is a totally functioning game but without sound. This pre-release version of the game has been dumped online for public to explore and enjoy, offering some notable differences from the final retail edition of the NES game.
Insight from the Video Game History Foundation
The VGHF recently examined the prototype cartridge in a detailed video. Frank Cifaldi, the founder and head of VGHF, has dedicated nearly thirty years to studying NES prototypes and was quite astonished. He said, “I’ve never seen anything like this,” after inspecting the cartridge’s internals. The prototype sports a sticker with a fake label matching Nintendo of America’s early NES packaging aesthetics from the mid-’80s.
Unique Storage and Design Aspects
The game data resides on stamped mask ROMs, which are permanent chips typically found in retail cartridges and marked with manufacturing dates. Usually, early prototypes used rewritable EPROMs, making this example unusual. Though Cifaldi mentioned these ROMs might be mock-ups, he was puzzled as to why a development version of Punch-Out!! would be assembled with these components.
Major Differences in Game Content
Unlike most NES prototypes that closely resemble final versions, this build shows significant early differences. The intro credits show fighters from the 1984 arcade Punch-Out!!, like Piston Hurricane and Pizza Pasta—characters replaced or removed in the retail version. Piston Hurricane was renamed Piston Honda, and Pizza Pasta was cut out from the North American version. Soda Popinski appears under his arcade name Vodka Drunkenski, likely a change for marketing purposes.
Unseen Characters and Hidden Content
Two mysterious fighters called Rockyhead and Mongol Khan appear in the game, but they’ve never been seen in any official release of Punch-Out!!. The playable roster in the prototype is limited to four opponents: Glass Joe, Bald Bull, King Hippo, and Don Flamenco. Other fighters like Von Kaiser and Great Tiger are present only in the game’s code and can be revealed via debugging, but they are not accessible to fight.
The Cartridge’s Journey and Public Release
This rare prototype console cartridge has an interesting history; it was found at a garage sale by a former Nintendo of America employee. It later received PSA certification and was auctioned by Heritage Auctions for $45,000. Many believed the game was kept hidden in private collections, but the lucky purchaser chose to upload the ROM online, allowing the Video Game History Foundation to analyze it thoroughly.






