Nitros Oxide

Nitros Oxide is the main antagonist of the 1999 racing game Crash Team Racing. He is an alien who challenges Crash Bandicoot, plus his friends and foes, to a racing tournament. If Oxide wins, he plans to enslave the planet's population and turn the entire planet itself into a concrete parking lot.

Crash Team Racing
In order for the player to race Nitros Oxide, they must first gather four keys to unlock the entrance to his spaceship. If Oxide lost the race, he'll challenge the player to obtain all the relics before racing him again. In a race, Oxide does not play fairly - he starts racing before the green light goes off and also barrages the player with beakers, TNT crates, Nitro crates, and bombs.

Crash Nitro Kart
Nitros Oxide also makes an appearance as a playable character in Crash Nitro Kart as part of Emperor Velo's squad of racers. He is only playable outside storymode, including his henchmen Zam and Zem.

Trivia

 * His name "Nitros Oxide" is a pun on his reputation as a racer.
 * In Crash Nitro Kart his name is misspelled "Nitrous Oxide".
 * In Crash Nitro Kart and Crash Twinsanity Oxide's head is way smaller than his previous appearances.
 * According to Oxide, he is the reason why there's no life on Mars. He raced against the inhabitants of Mars before he raced Earth and Mars lost, leaving it as a desolate, barren planet (this is said in scrapped dialogue).
 * If Oxide falls off the track in Crash Team Racing, he is helped by Uka Uka, who should ironically be against him.
 * In Crash Team Racing, Nitros Oxide has maxed out stats, but in Crash Nitro Kart, he doesn't have the maxed out state, probably because he's using a kart, not a hovercraft (and because he is not as important a character to the story). This is supported by one of Oxide's own quotes in CNK where he states that his kart is "Not bad for primitive technology."
 * Oxide was originally another evil scientist with a more standard human appearance. During development, the story was that he was trying to make the world faster and faster until the end of time, because of his obsession with speed. While further details about the original story are scarce, an old comic suggests Oxide would use a machine called the X Device.
 * In the cancelled game Cortex Chaos, Oxide was going to appear as Dr. N. Oxide along with N. Trance, N. Gin, N. Brio and many other new evil scientists in the league of mad scientists that was supposed to kick out Cortex from the group and have his rival N. Tropy as their new leader.