A Quest for the Secret Origins of Lost Video-Game Levels

How I returned a pirated Sonic the Hedgehog game cartridge to its original architect

Heidi Kemps/Sega

If I could have told my fifth-grade self that one day I’d be sitting in lobby of storied video game maker Sega’s central building, waiting to meet with Sonic the Hedgehog creator Yuji Naka, I think young me would have imploded with excitement.

Sonic creator Yuji Naka (Heidi Kemps)

And yet there I was, in the oppressively hot and humid Japanese August of 2005, preparing for an interview with Naka. I’d met and interviewed him a couple times before, but it had always been with a partner or in a roundtable setting. Naka had a reputation for being a difficult interview when he was still at Sega, but I had never seen him as aloof during my time with him—he had always been eager and willing to answer my questions. He was a creative type. He loved programming, relishing the ability to create entire worlds and realities from scratch through the simple act of entering words and commands into a computer. I respected him greatly, and I think he could see that I understood his underlying passion.

I was escorted by a spokesperson to Yuji Naka’s office several floors up. When we walked in, he smiled.

“Ah, it’s you.”

* * *

I wasn’t really like the other girls I knew in 1992. Instead of reading Tiger Beat and gossiping about boys, I read Electronic Gaming Monthly and gossiped with boys about games. I was the odd one out in my class, but I was also a repository of gaming knowledge. I had a place on the grade-school nerd social ladder that couldn’t be usurped.

Using my Christmas money that year, I had to make what seemed like a Sophie’s Choice to a middle-class 10-year-old: picking between a Super NES and Genesis as my first 16-bit console. After painful deliberation, I went with the Genesis, as it seemed like the better value to a cash-strapped preteen at the time. The first game I brought home with my new console: Sonic the Hedgehog 2. I replayed it constantly, exploring every stage again and again, finishing every level multiple times. When someone posted the level-select cheat code on a Prodigy gaming bulletin board well before it appeared in gaming magazines, I used the cheat to get to all of my favorite stages quickly. (I also made sure to print it out and share it in class, further cementing my nerd cred.)

I knew the game so well that, eventually, I realized something was missing. There was a piece of music in the game’s sound test that didn’t appear in the game itself. On top of that, there were screenshots in magazines of a stage I’d never encountered. Before the game’s release, Sega had sent out a batch of press images for media to use. A few screens stood out, portraying a strange, rocky-looking level called the Hidden Palace. I had sunk countless hours into Sonic 2, but I had never seen anything that even resembled these screens.

A few people wrote to magazines asking about the Hidden Palace, and editors would apologetically explain that the stage had been removed from the final version of the game. But, to me, there was a conspiracy afoot, a secret that Sega was keeping, and the proof was in those screens and that unused music.

Letters like this often appeared in '90s game magazines. (Game Players Sega Guide/GamePro)

Time passed, and eventually more Sonic games were released. They, too, had conspicuous bits of missing content. I moved on from obsessing about the Hidden Palace to trying to figure out why Mushroom Valley in the Sonic 3 stage select didn’t work. But I never forgot about it—and neither did an entire group of fans.

* * *

Around this time, one of the early types of console-game piracy had emerged in the form of game copier devices. These machines originated in Asia, and worked by copying the contents of cartridges onto floppy disks. The floppies could then be loaded and played back through the device as if they were a legit game cartridge. Even with the high cost of floppy disks, this was a far better value proposition than buying the games themselves.

If you didn’t have a cartridge to copy from, obtaining games for use with these devices was surprisingly easy: You just had to dial into underground servers and bulletin board systems using a PC modem to get game files to transfer onto disks, all while hoping mom wouldn’t try to make a phone call while a three-hour download was running over shaky dial-up. Copy the downloaded file onto a set of floppies, and presto: A brand-new, illicitly acquired game was yours, ready to play.

As the 16-bit generation waned, the World Wide Web emerged as a driving force of communication, especially among tech-savvy game nerds. And with it came a surge of interest in console emulation. Emulation, in computing terms, is simulating the operating conditions of one set of hardware on another—typically much more powerful—computer system, allowing for software to be run as though it was on a different platform. Emulators had already been written to allow classic arcade and console games to run in DOS, and were quickly adapted to the modern Windows platforms. The emulators being released for consoles like the NES and Genesis, though still early, offered functionality beyond what the consoles themselves could provide.

Emulators were worthless, however, without game files—known as ROM images—to run on them. A ROM image was an exact duplicate of a game, represented as a computer file. But plenty of ROMs already existed online, thanks to game copiers. Files that had once seemed obsolete in the new era of primarily CD-driven consoles were suddenly useful again, letting people load up and play classic games on modern computer systems.

* * *

As the Internet rose to prominence in the mid-to-late 1990s, communication evolved beyond Prodigy’s plain text bulletin boards, and the art of game rumormongering took new forms. While anybody could string together a free GeoCities fansite, getting your opinion taken seriously was a different matter. No longer could you simply make up a cheat code or claim to your classmates that you had an uncle that worked for Nintendo in Japan (“where they’re already up to Mario Bros. 18”)—online info spread fast and far, and rumors were more quickly debunked.

But it was through those fan sites—and through the underground emulation subculture—that interest in older games persisted. Passionate webmasters would detail as much as possible about their favorite classics, while visitors and contributors who stumbled across these pages could discover interesting facts they never knew about childhood games. For those who grew up loving Sonic, one of the key fixations was the Hidden Palace Zone. Old magazines were scanned, a scant handful of screenshots were painstakingly overanalyzed, and bizarre theories as to why it disappeared were bandied about.

By 1998, there had been a resurgence of interest in the Sonic franchise. Sega was about to release the Dreamcast, its last hope as a console manufacturing company, and with it the first new Sonic game in years. Memories of Sonics past were being rekindled, and fans were revisiting not just the old games, but the mysteries that went with them. Around this time, a string of rumors began causing a stir among Sonic devotees. Someone online was claiming that they had a friend with a really weird Sonic 2 cartridge, one with a different title screen and stage select code that let them play not only the Hidden Palace, but other stages with names like “Dust Hill,” “Wood Zone,” and “Genocide City.” It sounded like the typical made-up game hype that was everywhere during our childhoods—the mysterious “friend” with a special cartridge with different levels was a story heard a billion times before, and “Genocide City” sounded completely out of place in a game about cute animals fighting a mad scientist.

But the person behind this story, Andre Dirk, said he was going to prove it. He took some blurry Polaroid shots, scanned them, and posted them on a site called Secrets of Sonic the Hedgehog. In the era before Photoshop and digital cameras, this seemed to be as solid proof as a person could get. The Sonic fandom—and the larger Sega fanbase—was in a tizzy, with theories and speculation flying regarding this mysterious version of Sonic 2, all due to some blurry pictures.

The blurry photos that showed up online and stirred Sonic fan in 1998. (Andre Dirk)

If the Secrets of Sonic photos were like blurry images of Bigfoot to Sonic fandom, the ROM file that college-aged Sonic enthusiast Simon Wai found on a Chinese-language site in 1999 was the pelt of the legendary yeti itself. It didn’t look like much—a seemingly random string of letters and numbers followed by the file extension .smd, indicating it had been copied from a cartridge with a device called a Super Magic Drive. But when loaded into an emulator, the ROM’s true form was revealed.

Here it was, finally, the same version of Sonic 2 that was in those blurry pictures, now playable by anyone who could run a Genesis emulator on their PC. It was clearly a version of the game from early in development—stage layouts and enemy patterns were different, stage order and music was altered, and some levels were outright impossible due to physics that hadn’t yet been programmed. A few button presses revealed a stage select that opened up the mythical “lost” stages, including the now-legendary Hidden Palace.

It didn’t matter that these stages were near unplayable, featuring either impassible obstacles or, in the case of Genocide City, having nothing in them at all. After years of rumor and obsession, everyone with a PC could now play the Hidden Palace for all of two or three minutes before reaching an impassable slope. I was one of the many, many people who pounced on the ROM after it was discovered, and I savored the unfinished experience. This was a rarity, a playable glimpse into how a game—one that helped shape my childhood and my future career—was made. It was glorious.

Wai may have just found a ROM that had been sitting in a murky corner of the Internet, but the discovery had massive repercussions. It was more than just a strange validation for obsessive Sonic fans. The experience kindled a new interest—for me and for many other gamers—in learning how the games we loved were made. Individuals and groups devoted to finding, archiving, and distributing ROM images of unreleased and prototype games began to spring up. Hackers began delving into the code of classic game ROMs, finding hidden development relics and sometimes even candid hidden messages from the developers. And though he has long since moved into the world of professionals, Wai's name remains forever associated with a ROM called the “Simon Wai prototype.” (To this day, when you Google Wai’s name, the first few results will be about Sonic.)

A mystery lingered, however: Where did this ROM come from?

* * *

My interview with Naka was going well. He was jovial and eager to talk. It felt less like a Q&A and more like a conversation—the best possible outcome. Usually, game companies won’t book interviews unless the developer has a new product that needs promotion, while media outlets want to publish stories relevant to new releases. The need to feed into this coming-soon hype machine makes it surprisingly difficult to discuss a developer’s older titles. To justify the interview, I made sure to ask questions about the current crop of titles Sonic Team was developing at the time.

The truth, however, was that my interests lay elsewhere.

Here I was, having a solo interview with Naka for the first time. I finally had the opportunity to ask him things that had puzzled me since my childhood. I just needed to start with the right question. “There are entire websites out there devoted to looking into the code of these old Sonic games, finding all the things you guys were working on that didn’t make it into the finished product," I said. "What do you think of this?”

I got the sense that Naka, himself a fan of poring through programming code, may have been a bit flattered: “Wow, people do that? I didn't know. I guess I am pretty surprised at the level of dedication of fans on the Internet.”

“It could be problematic, though,” he continued. “If these fans get to the point where they’re engaging in activities that can hurt Sega, then that’s obviously an issue. For example, way back when we had a prototype cartridge of Sonic 2 that was stolen by someone. That one even had the old Hidden Palace level in it.”

Wait. I knew exactly what he was talking about. Did he know that what he’d just mentioned had been floating around through copied game floppies, pirated cartridges, and Internet emulation sites for years? The Hidden Palace Zone was well-known among the Sonic faithful, but did Naka know the extent of what fans had already dug up?

“Actually,” I replied, “that ROM’s data is out there. Online.”

Naka seemed pleasantly surprised. “What? You're kidding! Tell me more. I had no idea.”

Was this really happening?

“I have it here with me,” I continued. “On my laptop.”

“Do you, now?” He smiled again. “Somehow, I’m not surprised. You’re truly quite the fan.”

I turned on my laptop, booted up my Genesis emulator, and clicked on the file. It didn’t occur to me at first that I would be showing a top Sega executive my copy of an illegally duplicated development ROM on my PC. The thought didn’t even cross my mind until the title screen, the one different from what we all saw in 1992, appeared.

“Ahhhhh, yes,” said Naka, recognizing the early image.

“I guess this was found somewhere in Hong Kong, and it made its way online from there,” I explained.

“Are you sure this is a build with the Hidden Palace? I think maybe this one doesn’t have it.”

“No, it definitely does. It’s got the Wood Zone and Genocide City, too.”

Naka looked happy. A few clicks later, and the file was on a USB drive, and then, in the hand of the father of Sonic. The early version of a classic game this man had worked on—one that had been illegally copied many years ago and distributed through illicit means since—was now back in the hands of its creator. My years of searching, theorizing, and obsessing over a stage had led to this moment—I was giving something thought lost back to one of my personal idols.

Naka told me that the Hidden Palace—and those other stages—were scrapped due to the rough time constraints of game development, even though they already had graphics and designs ready to go for it. The prototype game itself had been stolen from a 1992 toy show in New York, or so Naka believed. From there, the data had been copied and distributed around Asia, sometimes passed off as the finished version of the game by unscrupulous retailers.

It had been a strange journey, one that began with a childhood obsession and ended with a reunion most unusual. I went back to my Tokyo hotel and told a few friends about what had happened. But I didn’t include the story of the file transfer into the interview I published—it didn’t seem appropriate at the time. Looking back on it now, almost a decade after our meeting, it still feels like one of the highlights of my game journalism career, and an amazing story about how things believed lost can return to us unexpectedly in the Internet age.

And the Hidden Palace Zone? It’s finally finished and playable in full for the first time ever in the iOS and Android versions of Sonic 2. Was it worth the 22-year wait? I can’t say, but it does feel like closure at last.