Kaze

Kaze, known as Yamikawa in the Japanese version, is a character in Yu-Gi-Oh! ZEXAL. He is a reformed student of Roku's Duel Sanctuary, as well as one of the Number holders.

Etymology
"Yamikawa" means "river of darkness", and he was said to possess some darkness in his Duels, and had a "Number" card, which amplify the darkness in their owner's hearts. His dub name, "Kaze", means wind in Japanese, a possible reference to his ace monster (excluding his "Number") "Blade Armor Ninja", which is WIND Attribute.

History
In the past, Kaze was a student at Roku's Duel Sanctuary, but after Dueling him and losing his faith, he grabbed a sword and slashed a statue of "Blade Armor Ninja", cutting it in half, after which he left the Duel Sanctuary and hadn't been seen since.

Yu-Gi-Oh! ZEXAL
After Yuma Tsukumo and his friends went to the Duel Sanctuary to help Roku out, Kaze showed up again and challenged his former master to a Duel, to which he easily won. He then ran inside and went to take the Legendary Deck, but was stopped by Yuma, who challenged him to a Duel.

As the Duel progressed, both continued to overthrow each others strategies and it was revealed that all of Kaze's hatred caused him to become possessed by a "Number" card, "Number 12: Crimson Shadow Armor Ninja". Kaze ultimately lost when Yuma Summoned "Number 39: Utopia" and defeated his "Number". He then went to slash the statue again, but was stopped by Yuma who convinced him that it was wrong, to which he apologized and began to study at the Duel Sanctuary again.

Yu-Gi-Oh! ZEXAL II
When Haru Tsukumo sent Yuma back to the Duel Sanctuary, Kaze answered the door and explained to him that Roku was away right now. In the Statue room, Kaze talked to Yuma about his frustrations and empathized with him by mentioning his own frustrations in the past. He told Yuma that he had been studying with Roku, and gave him two cards that Roku had left there for Yuma - "Overlay Chain" and "Overlay Bullet".

Deck
Kaze uses an "Armor Ninja" Deck, capable of quick Xyz Summoning. His ace monster is "Blade Armor Ninja". Whilst possessed, he used "Crimson Shadow Armor Ninja" after "Blade" was destroyed, but it was later absorbed by Astral. His cards are supported by a wide array of "Ninjitsu Art" cards.