Taiga Nobori (登 太牙, Nobori Taiga?, portrayed by Shouma Yamamoto) was born prior to 1986 as the first-born son of Maya, the Queen of the Checkmate Four, and the Checkmate Four's original King. He would receive the title of King at infancy after his father's death, caused by him being weakened by Otoya as Dark Kiva and the present day Kiva then Taiga, as an infant, reflecting the King's attack back at him, destroying him. Afterwards, he was spirited away by Maya to be raised by Mamoru Shima as a human child, wearing a glove over his hand to conceal his Checkmate Four crest. It would be while as a boy that he encounters Wataru Kurenai (who in fact is his younger half-brother) and the two become good friends until Taiga was spirited off, his childhood being under heavy watch. Along with learning of his true nature as the Fangire offspring of the previous King and Queen of the Checkmate Four, Taiga developed a disdain for humans as he attacks Shima, scarring his foster father's back before taking his leave. As the current King, Taiga intends to prevent the progress of humanity from moving forward to the point of becoming a problem for Fangires like with Ixa. The crime becomes even more unforgivable should the guilty party be a Fangire. When executing an opponent, he says, "The King's Sentence is given. It's death!" (王の判決を言い渡す。死だ！, Ō no hanketsu o iiwatasu. Shi da!?).
Though his Fangire form and name are a mystery, he displays impressive powers such as summoning a giant shadowy mass of vipers or conjuring up the Feathered Serpent called Kukulkan (ククルカン, Kukurukan?) and multiple giant Sagarc under a larger Mother Sagarc (マザーサガーク, Mazā Sagāku?) as his support. Even as an infant he displayed a great deal of power, proving able to deflect the Fangire King's attack back at him.
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