Leo Hyakujuu

Leo Hyakujuu was first introduced in the Duel Masters Victory V season of the Duel Masters Anime.

History
Leo is a new student who transferred to Katta Kirifuda's school. He constantly repeats the phrase "Ore wa Leo" (I am Leo"), which is referenced in the card-name of Codename Orewaleo.

He was a big fan of Duel Masters and YA.RA.SI band, but he also wanted fame. So one day he got on the stage of YA.RA.SI's concert in order to get attention of the world. At that same time Osamurai Van Osamu asked him who is he, he replied that he is a duelist. Osamurai showed him Coro Coro magazine with Katta on it as a new champion in the world of Duel Masters, Leo replied that he also want fame in Duel Masters as well.

Osamurai offered Leo the power of Zenith which can be used to defeat the champion and gain fame. Leo took that power and joined the same class as Katta in order to get the fame he wants.

Leo is the first character in Duel Masters anime who introduced Zero Civilization.

Duel Masters Victory V
Leo first appears to be a fan of Katta, later challenging him to a duel but Katta could not accept his challenge because he has to go somewhere important. Later Katta returned with Prin Prin, the Eternal to show her around the school and also introduced him to Leo. Leo as always tried to show-off in order to steal the spotlight but was left with no attention from the princess.

Leo saw Katta dueling against Jyotaro and when Katta was just about to take his winning turn Katta has to run to toilet and abandoned the duel Leo thought that could be his "Victory Mode" but it wasn't. Leo then dueled against Jyotaro using his new Unknown and Unnoise creatures. Leo easily defeated Jyotaro and impressed everyone including Katta who just returned from the toilet. Leo took the spotlight but also finally caught Katta's attention.

The next day Leo teamed up with Katta and Maria Ave as he was challenged by Jyotaro once again but this time he faced Jyotaro's team friend Kyusaku. Kyusaku did use a great combination strategy against Leo but Leo luckily got a Shield trigger which helped him destroy his combo of creatures on the field and easily won the duel taking out all of his combo creatures as well.

The next day, Mimi appeared in his class to tell them that the class was chosen to have a battle between two duelists broadcast live. Katta was confirmed as a participant in the battle as he was already known as the champion of the Duel Carnival Tournament from the previous season. His class later held a small tournament to decide the 2nd duelist. Leo won that tournament against Benchan in his final match by using Lionel, Zenith of "Ore" and will now duel against Katta. Before the match, he took Prin Prin, which causes Dragon Ryu to go to school with Katta on his card form as Off Course Kaiser "Dragon". Leo managed to get an upper hand, but Katta's Ogre Warrior Kaiser "Win" destroys his blockers and shields at the same time. In the middle of the match, Mimi accidentally knocked down the camera, which results that the duel won't be broadcast live. Leo refused to continue the duel and returns Prin Prin back to Katta.

At one time, during the school play rehearsal, Leo acts as the prince and have to kiss Snow White, who was Katta forcefully playing the role in place of Mei Midoriyama who fell asleep again, much to the class' amusement. Reading part of the script, he tells Katta about his next lines and actions, saying that they should do it once in a while for the play, much to Katta's horror and Benchan commenting that he have to like the modern concept of children's fairy tales. After Mei woke up and angrily throws stuff right at Katta after Katta woke her up, he commented that it will be less dramatic when approaching boys.

He uses the power of Zenith he obtained from Osamurai Van Osamu to control some of the students in the class to target Katta, however, he did not know that Osamu was using him as means to get Prin Prin. When Katta and his team realized that he was the one responsible for the incidents, he challenged Katta in order to obtain fame but got defeated. When YA.RA.SI band arrives, he walked away as he did not want to do anything with them. However, Seiya Kubo controls him, causing him to bring Maria Ave and Nai Minamimo to his location. After Seiya explained to Maria about Leo's connection to YA.RA.SI, Leo shown some sign of regret for making everybody involved in this mess. He dueled Seiya and won, getting more of the class back and reunites with the others who did not turn into cards and Katta. He apologized to the whole class after everything was over for causing this to happen due to his actions.

In the end, Leo lost to Katta and realized the fame Katta gets is the fame that he deserves. Leo's close friend Nai still thinks that Leo deserves more fame and so he challenges Katta for the sake of Leo.

Duel Masters Versus
He doesn't appear directly, but appears in a drawing book Katta had put in a time capsule two years prior to the story. He appears in there with many other characters such as Katta's classmates, Rei, and the Outrages.

In the manga, Katta remembers him and he is hopeful that Leo, along with the others of the 5th Grade Class, will be participating in the National finals. However, he was never seen.

Duel Masters Versus Revolution Final
He made his debut as a returning character in the season. In Volume 7 of the Versus Manga series, he is shown as a famous super star singer in YA.RA.SI. He decided to go back to his old town and meet his old friends on his holiday, but was surprised by Hamukatsu and Katta Kirifuda and a life-sized Briking, Deluxe coming at him.

In the anime series, it revealed that Leo went to Hollywood to become more famous. He was an actor in famous movies. He returned back to Japan, transferring to Katta's school and become the Student President of the school.

He has Damama as his creature spirit, with the Team Damama race of creatures.

During the time Katta removes the seal on his forehead, he was in his apartment reading his book when his card reacted, with the cards in his deck scattered in the process. It was when Damama appears in his physical form and Leo makes a partnership with him.

He went to the school with Nai through an underground vehicle, meeting up with Katta, Lulu Takigawa and Bucyake. The girls in the school tries to approach him, but Damama enlarges himself to scare them away, in which Leo was thankful for, Leo eventually explained to Katta he was here to get the position of the Student Council President. During the voting, he was tied with Maria Ave and have to duel to determine who will take the position. Leo reveals his Final Revolution card, Puchohenza, Mia Moja for Katta and proceeds to duel. In the final stages of the duel, he summons his trump card through Revolution Change, removing Maria's creatures from the battle zone and preventing the newly summoned creatures from attacking and blocking. He gains a win, earning a position in the Student Council. He eventually leaves the school grounds by helicopter with Nai and Damama for his next job.

Duel Masters Victory V
He is revealed to use the DMD-06 Rising Dash Deck: Counterattack Block! deck, based on the Light and Water civilizations.

His deck features the new Unknown and Unnoise races with Blocker creatures.

He later added additional Light and Unknown creatures. This is the first deck in which Zero Civilization was introduced to Duel Masters Anime.

He later added the following cards in his second battle against Katta;

He later added the following cards to fight against YA.RA.SI;

In his final duel against Katta he added:

Duel Masters Versus Revolution Final
In this series Leo uses a new Team Damama deck which contains Light, Nature and Light Nature Multicolored cards.

Trivia

 * His family name means "All kinds of animals" (百獣, Hyakujuu) and his given name "Leo" refers to the Zodiac Sign depicting the Lion, king of all animals. Also, his hairstyle is a nod to his given name.
 * He is printed on the Year 11 promotional cards, Idolmaster Leo and Truename Orekoso Foxstar.