Apparently, the merchant Torneko was the most popular character in Dragon Quest IV, so Enix decided to give him his own game series to star in. In 1993, Chunsoft created the first Dragon Quest spinoff: Torneko no Daibouken: Fushigi no Dungeon (Torneko's Great Adventure: The Mysterious Dungeon.) By taking elements of old Rogue-style PC games and updating them for the console audience, Chunsoft popularized a whole brand new type of game, which has since become their cash cow. Fushigi no Dungeon 2 featured their own character, named Shiren, which later exploded into its own franchise (one of which was released by Sega for the DS in 2008.) Several other franchises had their own Mysterious Dungeon games too, such as Final Fantasy (with Chocobo's Mysterious Dungeon) and Pokémon.
There were two more Mysterious Dungeon games featuring Torneko -- the second one was released for the PSone and was published in America under the name World of Dragion Warrior -- Torneko: The Last Hope, where it was lambasted by western critics and gamers alike. The third was released for the PlayStation 2. Both the second and third games were ported to the Game Boy Advance. In 2006, a fourth Dragon Quest-related Mysterious Dungeon game was released: Shounen Yangus Fushigi no Dungeon, featuring a younger version of everyone's favorite brute Yangus from DQVIII, along with a few other characters, like Red the female bounty hunter. While all of the Torneko games were done by Chunsoft, this one was actually developed by Cavia, known for Drakengard and Bullet Witch.
In order to ride the Pokémon wave, Enix created Dragon Quest Monsters, which are primarily centered around portable platforms. It's more than a cheap cash-in -- as the series allowed you to capture monsters and use them in your party back in DQV. Plus the series had built up an impressive array of amusing monsters, and building up an army of slimes and drakees will always be pretty fun.
It also allows you to fight and collect major boss monsters, like Baramos and Zoma from DQIII, Esterk and Pizzaro from DQIV, Mirudrass from DQV, and Deathmore from DQVI. The games also include renditions of the overworld themes from DQI -- VI. The first game was released on the Game Boy Color and puts you in control of Terry in his search for Milayou, who are still children here. It's meant to be a sidestory/prequel to Dragon Quest VI, and a lot of references like these were list since that hadn't been translated for the U.S.
The second game was divided into two releases -- Tara's Adventure (Iru no Bouken) and Cody's Journey (Ruka no Tabidachi.) All of these were released in English by Eidos. There was also a Japan-only remake for the PSone that compiles all three releases and features enhanced graphics (though they're still 2D) and better music.
A third installment was released only in Japan under the title Dragon Quest Monsters: Caravan Hearts for the Game Boy Advance in 2003. This one stars a child version of Kiefer from Dragon Warrior VII. The fourth entry, Dragon Quest Monsters: Joker was released for the DS in America, Europe and Japan in 2007, and features cel-shaded 3D graphics, so it looks like a downscaled version of Dragon Quest VIII. It's also the first Dragon Quest game which ditches random battles, since you can see your enemies when running around. These were all created by infamous shadow development house TOSE, who's known for stealthily created or porting games for bigger publishers.
The Slime Mori Mori series consists of two action-adventure games for portable platforms. In each game, you take control of a little slime, whose village has been attacked by the Tails Brigade (called the Plob in the English version), a group of evil Platypunks out to cause mischief. It's basically a Zelda-style game, as you search mini-dungeons to save the inhabitants of your village, who give you various items to help you on your way. The original GBA title, Slime Mori Mori Dragon Quest: Shougeki no Shippudan" (Exciting Slime Dragon Quest: The Attack of the Tails Brigade) was only released in Japan.
The second, subtitled Daisensha to Shippodan (The Great Tank and the Tails Brigade) for the DS, features nearly identical graphics, music and gameplay, though it features brand-new levels and a new story. The big addition are the tank battles, where you use different items you've collected to load cannons and attack a rival tank. This one was released in America under the title Dragon Quest Heroes: Rocket Slime, and features an outstanding localization with lots of amusing writing and some inventive names. How could you not love a nun slime named Mother Glooperior, or a gigantic tree tank named Chrono Twigger? They're both pretty simple, easy games, but it's fun peering into a world where the Dragon Quest monsters are the good guys. Like the Monsters series, these were both developed by TOSE as well.
Kenshin Dragon Quest: Yomigaerishi Densetsu no Ken (Sword God Dragon Quest: The Resurrected Sword of Legend) is a standalone plug-in toy game system released in Japan in 2003. It featured a shield, which would plug directly into your TV, and a sword, which you'd slash at the TV to kill monsters. The technology was later adapted by Hasbro for use in some its titles, like The Lord of the Rings: Warrior of Middle Earth and Star Wars Saga Edition Lightsaber Battle Game.
The idea was fully fleshed out and into turned into a full fledged console release for the Wii, called Dragon Quest Swords: Kamen no Jouou to Kagami no Tou (The Masked Queen and the Tower of Mirrors, an accurate translation of the subtitle for once), developed by Eighting. As can be expected, you wield the Wii remote like a sword and slash at monsters on screen. It looks sort of like Dragon Quest VIII, though without the cel-shading. It's still more of a short, on-rails action game with a few RPG elements rather than a full RPG -- there's only one town, the story is brief and it only takes a few hours to finish. But it's the first Dragon Quest released in Japan that features full voice acting.
There are three Dragon Quest anime series. the first, Dragon Quest: Yuusha Abel Densetsu (The Legend of The Great Hero Abel), was a full TV series chronicling an original story in the series. This one was actually licensed for English release by Saban Entertainment, though most networks tended to bury it during early, early morning Saturday cartoon blocks. Since the American audience wasn't familiar with the Toriyama artwork from the games, the only real connection seemed to be the music, and the fact that the main character had a mini-slime that traveled with him. (There are several name references to the games, but these were mostly to Dragon Warrior III, which hadn't come out in America then. For example, the bad guy named is named Baramos.) Only 13 of the 43 episodes were translated. You can find most of the English episodes on YouTube.
A second series called Dai no Daibouken (Dai's Great Adventure) was based off of a manga, and is again an original story not based on any of the video games. There are a total of three movies and a TV series with a total of 46 episodes, all released in the early '90s. None of these officially came to America, though they were translated for released in certain European countries. The main character was renamed Fly for these releases. You can also find some of these on YouTube, and there are English fansubs floating out of the movies.
The third is named Roto no Monshou (Emblem of Loto), a single movie, which was based off a long running manga series. Again, it's an original story, though it ties in closely with the world and events from the original Dragon Quest trilogy.
[The author thanks to Aeana for the aid, as well as Red Scarlet, Error, and anyone else from NeoGAF, whose guides and threads provided fruitful research for this article. An adapted version of this feature was originally published on the HG101 website.]