Nintendo is one of the big names in the world of video gaming. They've been making games and consoles for quite some time and have quite a few really popular games with really unique gameplay elements. Some of these games that have been released over the years have included some unique features that are exclusive to these games and that many gamers might not know about.

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From accessories that only work with a single, specific game to games that have an unusual feature that doesn't appear in other games, Nintendo has gotten creative with the secret features of some of their games over the years. This was especially true with their more retro consoles like the Game Boy and original Nintendo DS.

To see 10 retro Nintendo games with unique features, keep reading!

10 Nintendo DS Memory Expansion Pak

The Memory Expansion Pak isn't a feature, but an accessory that exclusively worked with a single cartidge for the Nintendo DS. This catridge is the Nintendo DS Browser. This accessory could be plugged into the Nintendo DS when the Nintendo DS Browser was plugged in and would add 8MB of RAM to the device.

This is the only piece of software that was able to utilize this accessory, making it a pretty unique feature for this cartridge. Considering this was out at a time when Internet browsing on the go wasn't as common as it is now with smartphones and tablets, this was a pretty interesting accessory for the DS.

9 Learn with Pokémon: Typing Adventure

Learn with Pokémon: Typing Adventure is an educational typing game that was released in Australia, Europe, and Japan for the Nintendo DS. It teaches the player to type on the included bluetooth keyboard by having them type out different phrases and words that appear on the DS' screen.

This game is the only one released that utilized the wireless keyboard. The DS itself actually didn't have bluetooth connectivity, so this game is unique because of the fact that a bluetooth adapter is built into the cartridge itself.

8 Face Training

Face Training is a game that was released on the Nintendo DS exclusively in Japan with a port coming to the Nintendo DSi in other regions later. This game would use a camera to scan the user's face and guide them through facial exercises, designed to help strengthen and tighten the user's facial muscles in order to give them a more youthful appearance.

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If you're familiar with the Nintendo DS, you'll know that this handheld console actually didn't have a camera. While the DSi did, there wasn't a port of this game onto that console until later. So, how did this game work on the original DS? It used a peripheral called the Faceningscan that was only released in Japan. It was plugged into the Nintendo DS and then had an external camera that would only work with Face Training.

7 Pokémon Stadium

Players that are serious fans of the Pokémon franchise likely played Pokémon Stadium on their Nintendo 64. One thing that only the most dedicated fans of the series will know is that the game would also allow you to play other games in the franchise like Pokémon Yellow through your Nintendo 64 on the big screen.

After visiting Game Boy Tower and plugging in their Transfer Pak, the player could plug in their different Game Boy Pokémon games and play them on their TV instead of just on their small, handheld console.

6 Morita Shogi 64

Morita Shogi 64 is a virtual board game version of the ancient Japanese game Shogi. This game was released exclusively in Japan on the Nintendo 64 and is unique because of the small port located on the top of the game's cartridge.

Even though this game was released in 1998, this game is unique because of the fact that it let players play competitively online. Playing online with other people around the world wouldn't become commonplace in the world of gaming for quite a while, so this game was truly ahead of its time. This functionality was optional, but the port at the top would allow players to plug an ethernet cable into their modem to connect to the game's servers.

5 Super Mario World 2: Yoshi's Island

Yoshi's Island snes

The Super FX chip is a processing chip that was installed in a few different SNES games like Star Fox in order to help it have more powerful processing and better graphics. Games like Star Fox were pretty open about using this chip and even used it as a selling point to appeal to customers.

But, there's one game that used a later version of the Super FX chip that didn't mention having it at all. Super Mario World 2: Yoshi's Island is well-known among fans of the Super Mario franchise because of its unique graphics and pseudo-3D effects. These were all possible because of the fact that it used a Super FX 2 chip, but for whatever reason, Nintendo didn't use it as a marketing point the way they had with previous games.

4 Gyromite

Gyromite is one of only two games to support Nintendo's R.O.B. Although this may already seem like a bit of interesting trivia for some Nintendo fans, that's not the only thing that makes some copies of this game special.

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Due to a rush for Nintendo to put this game out in time for the holiday season, Nintendo decided to just ship Japanese Famicom copies to North America in order to meet their October release date without any delays. But, Famicom games don't play on NES consoles. To fix that, Nintendo built in a Famicom-to-NES adapter into some of the early cartridges. This makes these cartridges sought after by collectors and by people that want to use that adapter in other Famicom games.

3 Space Invaders

Space Invaders is a Game Boy port of the arcade classic by the same name. This game is one of many that could be plugged into the Super Game Boy accessory and then played on the big screen on the SNES.

Instead of just playing the Game Boy version of the game on the big screen like most other games that are plugged into the Super Game Boy accessory, this game is completely different. When the player starts the game up on their SNES, they're given the option to either play the Game Boy version or the SNES version of Space Invaders.

2 Pokémon Crystal

The Mobiel Game Boy Adapter was released in 2001, exclusively in Japan. This device would allow the player to hook their Game Boy Color up to a compatible mobile phone. This would effectively work as a modem for the Game Boy Color and would kind of allow them to play their games online.

Unfortunately, this peripheral wasn't all that popular or successful because of the fact that it was mostly only compatible in a major way with a single game: Pokémon Crystal. Players were able to trade and battle with other people this way.

1 Singer Izek 1500

This is less of a unique feature of a single game and more of a unique feature of an entire console, but is such an unusual one that it simply can't be left off this list. The Singer Izek 1500 is a sewing machine that could be controlled by the Game Boy Color for people that had a specific cartridge and all the cables to hook it up to their sewing machine.

Nintendo was working on a similar knitting cartridge for NES, but it doesn't seem like they ever went forward with it after some early announcements. Still, this unusual accessory that allowed players to plug in a game and use it to save sewing and embroidery patterns through their Game Boy Color was definitely an interesting one.

Next: The 10 Rarest Nintendo Consoles (& How Much They're Worth)