Vector

Vector the Crocodile, usually just called Vector, is a character in the Sonic the Hedgehog series, and the leader of Team Chaotix. He and his team will do anything for money, as long as it doesn't break the law. He is a playable character in Mario & Sonic series. He is a power character. The other members of Team Chaotix, Espio the Chameleon and Charmy Bee, are referees in this game. He is the only playable character in Team Sonic to not have his own trophy in Super Smash Bros. Brawl. However, Vector does appear as a collectible Sticker. In Mario & Sonic at the Olympic Games and its Winter version, he takes his model from Sonic Heroes and was voiced by Dan Green, who also voiced Knuckles the Echidna.

Mario & Sonic at the Olympic Winter Games
In the Adventure Tours mode in the Nintendo DS version, Vector the Crocodile is first mentioned by Charmy Bee when Mario, Sonic the Hedgehog, and Toad run into him when the bee refused to let the trio get pass him. Toad then tells Charmy they will let him know when they see Vector.

Later in Icepeak, Vector is seen next to a mission sign and he knows Mario and doesn't know that if Sonic is with him. He tells the trio he will join the group if Donkey Kong defeats the music-loving crocodile in a match of Short Track 500m. Once Donkey Kong defeats Vector, he then joins the party.

Toad then tells Vector that Charmy needs to see him back in Cubyrinth. When they arrive in Cubyrinth, Charmy tells Vector in order to open the gate, he must engage in a quiz based on Real and Dream Winter Olympic sports and the islands of the snow spirits. He tells him if he gets 5 questions correct within 45 seconds, he will open the gate and let them through. Vector succeeds, and they go through.

Espio is seen when he tells his friend to let him know how many more whitestones are there in Sparkleton, Cubyrinth, and Blizland. When all the whitestones are found in those islands, he gets surprised that there's none left when the player collects all of them.

Mario & Sonic at the London 2012 Olympic Games
In the story mode in the Nintendo 3DS version of the game, Sonic arrives at the Volleyball court and is almost killed by Bowser as he surprise attacks. Knuckles the Echidna and Vector the Crocodile helps out and challenges him to an event and lets Sonic go. They defeat him and he runs away to escape before Sonic crushes his machine. The Wild Ones destroy the machine and Sonic and Tails move on.

Profile
''Rough-and-tumble Vector is a crocodile that loves money, which means he wants that Gold Medal more than anything. With incredible Power skills, he'll perform well in the throwing events and, given his unique swimming stroke, can excel in the pool as well.''

Profile
''Vector the Crocodile is large and strong, and heads the Chaotix Detective Agency. Vector's Head Slide abitily on the Wii and DS, and Gum Balloon ability on the DS will put him toe-toe with the other contestants as he goes for #1!''

Trivia

 * Coincidentally, Vector bears a resemblance to the Kremling species.
 * Vector, along with Charmy Bee, has only appeared in three games before the Mario & Sonic games: Knuckles' Chaotix, Sonic Heroes, and Shadow the Hedgehog.