Kai Ozu

"The Burning Flame Element! The Red Magician (Legend) MagiRed!"

Kai Ozu is the youngest of the Ozu Family, he is the Red Mage, MagiRed. He uses his proficiency with alchemy and his power over the element of fire to fight evil.

Design
He wore red spandex with a short red cape, which was an outline for a large "M", which went all the way down to his boots. His belt buckle was in the shape of an "M" also. His helmet bore the symbol of the Phoenix.

Magiranger
17 (23 as of Gokaiger) years old and the youngest of the Ozu siblings, Kai is a Red Mage, a wizard who has power over the Burning Flame Element (燃える炎のエレメント, Moeru Honō no Eremento). Despite being the youngest, he still follows the tradition of his fellow Red Rangers of being the team leader. He's a sophomore student who's into soccer and fights a lot with his older brother Tsubasa.

He's straightforward and impulsive, which often leads to him making mistakes, but he is also kind-hearted and very brave for his age. He hates to be babied and wants to be treated like an adult. He was most upset about his mother's apparent death by Dark Magic Knight Wolzard, and swore vengeance for it, until he learned that Wolzard was his father.

During the course of the series, he inherits many of Isamu's techniques, mainly his "Blazing Storm" and lives by his father's saying "Chance is something you make yourself."

His primary attack is "Red Fire", where his body is engulfed in flame creating a Phoenix which burns any adversary it flies through. As Red Mage Legend MagiRed (レジェンドマジレッド, Aka no Mahōtsukai Rejendo Majireddo), Kai's "MagiBolt" summons a torrent of fire, which is more powerful than Red Fire. In the special "Tokusei Magiranger Special", Kai drops his MagiPhone into the Mini Garden Spring while dueling with MagiShine and the Goddess of the Mini-Spring gives him the option of getting either a Silver MagiPhone or the Golden GripPhone and so he lies to gain the Golden GripPhone and with it, the ability to become Heavenly Hero KaiShine (天空勇者カイシャイン, Tenkū Yūsha Kaishain).

As KaiShine, he wears MagiShine's armor, with a red neck scarf in place of MagiShine's flowing golden cape. However, he accidentally transforms himself into a duplicate of Hades Beast Spider and since he lied to get the Golden GripPhone, its magic is closed off to him, but fortunately the Goddess of the Mini-Spring is able to use magic to restore him when he pledges to never be dishonest again and is returned his normal MagiPhone. In the end of the series, he becomes a sort of a liaison between the "Surface World" and Infershia. He also now dresses in his father's traditional Magitopian robe and so foreshadows that he will carry on his father's legacy as a great warrior of magic. AkaRed in GoGo Sentai Boukenger vs. Super Sentai transformed into MagiRed and fought against Chronos, Duchess Org Tsuetsue, Sorcery Priest Meemy and Arch Priest Gajah.

Also, In the Special "Mahou Sentai Magiranger Vs. Tokusou Sentai Dekaranger" it is shown that Kai carries a picture of Yuka Yamazaki-san, whom he loves, displayed in his Magiphone when Ban asked him that if, in ten years, on the next Fantastic Happy Day, If they themselves would have families of their own.

Gokaiger
A few years later, Kai fought alongside not only his own team, but every single Sentai ranger in existence, against the Empire of Zangyack when it attacked the Earth in the Great Legend War. After fighting against hundreds of Gormin and their Zgormin commanders. AkaRanger noticed the fleet moving towards them, he gathered all the Rangers together and gave them the order to sacrifice their powers to wipe out the first invasion's armada.

When the Gokaigers landed on Earth, their guide Navi told them to find "A man dressed in black". This man turned out to be none other than Kai, now 23 years old and calling himself "A magician who has forgotten his magic" and challenged Gokai Red and Gokai Green. With assistance from Heavenly Saint Flagel, Kai helped Gokai Green realize the "true power of the Magirangers", which turned out to be courage. He revealed to Marvelous that he could only gain the Greatest Treasure in the Universe once he unlocked the greater power of the Ranger Keys. It's also alluded to that he might have given GokaiOh the power to transform into Magi GokaiOh.

After the defeat of Ackdos Gill, Captain Marvelous returned all the Ranger Keys to the former Sentai heroes. Since his sister Houka Ozu got her powers back, it is assumed he got his powers back as well.

Super Hero Taisen
Kai, alongside his team (MagiShine, MagiMother, and Wolzard Fire were absent), among the majority of the Super Sentai heroes, was caught up in the "Super Hero Taisen" incident which eventually resulted in the Super Sentai teams and Kamen Riders joining forces to defeat both Dai-Zangyack and Dai-Shocker.

Ranger Key
The MagiRed Ranger Key (マジレッドレンジャーキー) is Kai Ozu's personal Ranger Key and what became of his powers after she along with the rest of the 34 Super Sentai sacrificed their powers to end the Great Legend War.

This key along with the majority of the Ranger Keys were collected by the Red Pirates and later used by the Gokaigers. The MagiRed Ranger Key was mainly used by Captain Marvelous (Gokai Red), who used it to fight as MagiRed. It was also used by Luka Millfy (Gokai Yellow) and Ahim de Famille (Gokai Pink) on several occasions.
 * Ahim became MagiRed as part of an all-red Gokai Change when the Gokaigers traveled to the past and fought against Shitari of the Bones and his Gedoushu during the Goseigers' team-up with the Shinkengers.
 * When the Gokaigers became the Magirangers in their fight with Action Commander Shikabanen and his Zangyack force.
 * Luka became MagiRed as part of an all-red Gokai Change in the Gokaigers' fight with Action Commander Bongan.
 * When the Gokaigers became the Magirangers in their fight with Action Commander Salamandam.
 * Ahim became MagiRed as part of an all-red Gokai Change when the Gokaigers fought against Basco's Gokai Red Ranger Key Clone while Marvelous was incapacitated.
 * When the Gokaigers became the Magirangers while fighting Insarn.
 * While fighting against Kamen Rider Fourze Fire States.

After Zangyack were finally defeated, the Gokaigers gave the Ranger Keys back to their rightful owners. It is presumed that Kai received his key and became MagiRed once more.

Trivia

 * At the age of 17 in 2005, he was the youngest Red Ranger in the entire Sentai Series and the only Red Ranger who was below 18.
 * He is the first Ranger Legend to give his team's Greater Power in Gokaiger.
 * Kai is the first male, as well as the only Red Warrior, to have a Phoenix motif.
 * The three others were all female and their team's Pink.
 * Coincidentally, all four Phoenix Rangers have three-letter first names.
 * Gorou Hoshino also possessed a phoenix for his mecha, but is more known for his Star Motif.