Sonic Adventure 3/Turbo the Mole

"I betcha those Chaos Emeralds are gonna be mine, and then once y'all rascals know it, that there Demon Emerald of mine's gonna take all da' Master Emerald's! Cha-cha-cha, HAHAHAHAHAHA!!!!!" (Turbo to Sonic and Knuckles in Sonic's Story Mode playthrough

About Turbo
Turbo the Mole (Japanese: Nitro the Mogura) is a 15-year-old anthropomorphic mole with similarities to Knuckles, although the two are of a different species, and Turbo is the watchful protector of the Demon Emerald, an ancient, abandoned Super Emerald that Dr. Robotnik restored and brought back to its evillest state, handing it over to the latter. Turbo is actually a fanmade character by Beecanoe, originally made for the Epic Saga franchise. However, Sonic Adventure 3 marks his full and official debut, having more of a detailed backstory and reason as working for Dr. Robotnik and Metal Sonic (who has, yet again, been reprogrammed into its ruthless, cold self). In Sonic Adventure 3, Turbo is voiced by Nobuyuki Hiyama in Japanese and Yuri Lowenthal in English.

Sonic Adventure 3
Turbo the Mole is generally selfish, boastful, and highly rambunctious, often wanting to do things independently and always acting before thinking... Considerably, in the original Japanese version, He ends the majority of his sentences with "Temei", a rough version of the word "you" and doesn't address anyone with honorifics but himself. Through cutscene footages, Turbo is shown to be guarding the Demon Emerald and swearing vengeance against Sonic and Co. (The only time he doesn't do this is when you play his Story Mode and no one elses), always hatching plans with the help of Metal Sonic. Also, Turbo has a tendency to use Texan dialect, with the said character even bearing a Southern accent (at least in the English version)... The most famous/infamous for this is his constant "YEE-HAW!!" battle cries, as well as often wearing some sort of ten gallon hat before Turbo makes a move! Turbo the Mole does, however, have a soft side: he constantly works with Metal Sonic on many occasions, even having him use a communicator through Dr. Robotnik's speech radar. Also, when the Demon Emerald is captured by Knuckles in order to purify the evil, Turbo finds no more need for the Demon Emerald and will eventually settle the score with the heroes! Other than that, Turbo is a villain...

Epic Saga
Turbo the Mole really doesn't have much of a role in this franchise, despite having a debut... Turbo shares nearly all the similarites to his Sonic Adventure 3 counterpart, save for personality-wise: for one, Turbo the Mole has a tendency to never leave Beecanoe's side at all, proving his loyalty! Also, Turbo is more of a mechanic here (compared to Epic Saga, in Sonic Adventure 3, Turbo has little or no experience with technology or anything... this is a bit of a recurring gag in the game), with skills that slighty match up to Genius Guy #445. Beecanoe, Geniusguy445, or ETG can add or change more in this section if necessary!

Trivia

 * Turbo's theme in Sonic Adventure 3 is "Stranger Walkin'!", which is a remastered and remixed version of the Launch Base Zone Act 1 music from Sonic the Hedgehog 3 & Knuckles (http://www.youtube.com/watch?v=0XdKBv1UApY&feature=related)
 * In terms of gameplay in Sonic Adventure 3, Turbo the Mole can run and climb walls significantly faster than Knuckles (nearly rivaling Rouge the Bat in this title)... He also, while unable to glide, can dig underground and drag nearby enemies down and attack and can breathe underwater for essentially six hours in nearly each of his playable stages.
 * In all subsequent Epic Saga appearances, Turbo's english voice is instead provided by Johnny Yong Bosch, whereas in Sonic Adventure 3, Yuri Lowenthal provides speaking parts... This is because the Turbo in the Sonic Universe is different than the one from the Epic Saga Universe