In the 1990s, Sega Was Obsessed with Things That Locked Together

Sonic & Knuckles

People were obsessed with a lot of weird stuff in the 1990s. This was the decade of the Beanie Baby craze, as well as Jnco jeans, Animaniacs, and Tamagotchi digital pets. In the 90s, I was obsessed with Weezer and Resident Evil.

Sega, however, had one of the weirdest 90s obsessions of them all — the company was super into things that locked together. (They also put out a laser tag set in 1992 called the Sega Lock-On, but since it doesn’t actually lock onto anything, I won’t talk about it here except to acknowledge that I am aware of it.)

Anyway, here’s a brief history of Sega’s relationship with lock-on technology.

Sega CD (Mega-CD)

Sega CD

The Sega CD (or Mega-CD) — which launched in Japan in 1991 (it hit the States in 1992, and Europe in 1993) — was an add-on to the Genesis that could read compact discs. Not only could you play your favorite music CDs on this bad boy, but the Sega CD could read game discs as well. At the time, putting games on CDs instead of cartridges meant more memory to hypothetically make bigger and better and more graphically complex games.


The Sega CD’s game library was heavily reliant on FMV games. In case you’re not familiar, FMV (full-motion video) games feature live-action performances by real actors. Some of these games play out like interactive movies, though a lot of them are simply rail shooters with live-action cutscenes in between actions sequences. A quick scan of the Sega CD’s game library (which includes Sewer Shark, Night Trap, Wirehead, Who Shot Johnny Rock?, and Tomcat Alley, just to name a few), shows just how FMV-heavy the console’s catalog was.

Sewer Shark - 16 Barrels of Fun

This was a gamble that didn’t pay off. While FMV games are still around (and many of them are very good), this has always been one of gaming’s odd niches. It certainly seems like Sega was expecting FMV games to be the next breakout thing, but that’s not what ended up happening. The Sega CD would lose its relevance pretty quickly as the next generation of consoles introduced 3D worlds and reinvented old genres.

The Sega CD was physically bigger than the Genesis, so when you hooked the two together, you ended up with this super-wide, ridiculous-looking console that sat there next to your TV, which was also oversized because is was the early 90s and we were still using CRTs. By 1994, the bulkiness problem was solved with the release of the Sega CDX, which is compact and kind of awesome. Of course, the Sony PlayStation would launch in Japan that same year (and in the United States in 1995), and the Sega CD would begin its sad fade into obsolescence.

While I paid way too much for a Sega CD back in the 90s, I can’t be too upset about it in retrospect. After all, the Sega CD brought us Sonic CD and Lunar: The Silver Star, which are two of my favorite games of all time (though the PlayStation version of Lunar is superior), as well as a tragically overlooked Jurassic Park game.

Sonic & Knuckles and Lock-On Technology

Sonic and Knuckles Cartridge

I would have loved to have been a fly on the wall in the pitch meeting for the weirdly designed Sonic & Knuckles cartridge, which released on October 18, 1994.

As a side note, I initially thought the lock-on version was exclusive to the United States, but it wasn’t: Japan got a lock-on version of Sonic & Knuckles the same day it came out in North America, and the flavor text on the box was absolutely incredible. (Japan got an additional version of the game in 1997 in the form of The Sonic & Knuckles Collection, which featured both Sonic 3 and Sonic & Knuckles, as well as the locked-on version, Sonic 3 & Knuckles).

The cartridge included the game Sonic & Knuckles, but it also had a cartridge slot built into the top of it. You could plop your copy of Sonic 2 or Sonic 3 into that slot and all of a sudden you were able to have Knuckles as a playable character in those games. Sega called this Lock-On Technology (with a TM because of course they would try to trademark that).

If you inserted the first Sonic the Hedgehog game into the Sonic & Knuckles slot, you’d open up a game that later became known as Blue Sphere. Basically, this was a series of stages similar to the sphere-swapping bonus stages in Sonic 3, though it’s said that these ones are randomly generated.

Blue Sphere

Additionally, most non-Sonic carts would allow you to play just a single stage of Blue Sphere when locked onto Sonic & Knuckles.

To my knowledge, Sonic & Knuckles is the only game that had the lock-on feature built on the game cartridge. If I’m wrong about this, please let me know in the comments; I would love to explore more of these games.

This is one of the most interesting takes on retro DLC I can think of — Sega had figured out how to add content to games in a world before the widespread adoption of the Internet. And they figured out how to charge gamers an arm and a leg for that content as well (if you bought both Sonic 3 and Sonic & Knuckles at their launch-day MSRPs, you’d be paying a whopping $139.98 before tax… in 1990s dollars).

If the concept of locking a cartridge into another cartridge doesn’t sound quite ridiculous enough, a YouTuber by the name of plaistar101 experimented with adding a copy of Sonic & Knuckles into another copy of Sonic & Knuckles, and then putting a copy of Sonic 3 into that. Oh yeah, you can do that, though, as plaistar101 discovers, there’s not really a point to it.

As absurd as the stacked-cartridge concept might be, Sonic & Knuckles was actually a pretty good game (though I would argue it was inferior to Sonic 2, Sonic 3, and Sonic CD), and it had some seriously badass box art.

Sonic & Knuckles

Just look at that thing. Gone are the cartoony renderings of Sonic game worlds and characters, replaced by a simple logo on a black background. It has an air of mystery to it, as well as an overwhelming a sense of confidence. In fact, I’m tempted to call this the best Sonic box art ever made. I promise you, the first time I saw that box on store shelves as a kid, my head practically exploded.

Sega 32X

Sega 32X

What if, instead of buying a new gaming console, you could just keep upgrading your current console by adding new components to it? With add-ons for the Genesis, Sega attempted to answer that question not once, but twice.

If you’re imagining this being similar in concept to, say, upgrading a stick of RAM in your desktop computer, think again. This was more like a broken Voltron toy that was a hand-me-down, so it was missing a bunch of essential components and you never really figured out how to put it together. Wait, maybe a better analogy is the famous Winchester Mystery House, the house that was perpetually being added to from 1886 to 1922.

Well, maybe we should skip the analogies for now.

After already releasing an expansion to the Genesis in the form of the Sega CD, Sega tried to see if they could get away with a second expansion, the 32X. The 32X would allow you to play 32-bit games (instead of those lousy ol’ 16-bit games). And yes, the 32X had its own native library of games, though you could also play Genesis games (it would be strange if you couldn’t play Genesis games, seeing as the 32X wasn’t playable without a Genesis).

Now, if for some reason you’re thinking this was probably a successful piece of hardware, let me remind you that the 32X launched in Japan in December of 1994, about two weeks after the Sega Saturn launched there. The world was ready to move on to the next generation rather than pay a bunch more money to be stuck in the previous one.

So… not successful then?

Well, no. If you take all regions into account, there were only 40 games released for the Sega 32X. Wikipedia lists 77 games that were supposed to release on the 32X but were cancelled, meaning there were almost twice as many games cancelled for the 32X as there were games that released for it. Or, to put that another way, almost 2/3 of the 32X’s game library was cancelled.

Looking back, it seems odd that Sega would keep recycling the same general concept with such diminishing returns. As I mentioned earlier, I can sort of see where there heads were at with Sonic & Knuckles as a way to expand beloved games beyond the scope of a single cartridge. But the 32X still mystifies me to this day.

It did have Doom, though, so of course I wanted it as a kid, to the chagrin of my religious parents.

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