Checkmate Four

The Checkmate Four (チェックメイト・フォー) are the four most powerful members of the Fangire race, each bearing a tattoo of the chess piece they are named after. These four Fangires receive the titles of Rook (ルーク) the hunter, Bishop (ビショップ) the keeper of Fangire laws, and Queen (クイーン) & King (キング), the rulers of Fangires. In 1986, the Checkmate Four were based in Castle Doran. By 2008, only Bishop and Rook remained as they recruit a new Queen and King.

Lion
The first of the Checkmate Four to appear in the series, he can shoot out needles from the tip of his fingers while in his Fangire form. Rook's actions in 1986 include the murder of Yuri's mother and the slaughter of the Wolfen Race. Being a strong Fangire, the Rook defeats Ixa and Jiro in early confronations prior to his resting after his near-death experience at the hands of Yuri and company. In 2008, after awakening from his rest, the Rook has somehow lost his memories and befriends Wataru and Shizuka, and they call him "Dai-chan" (大ちゃん). The Rook later regains his memories as a Fangire upon seeing the site of one of his 1986 battles. Easily defeating Kiva, he summons a golden Sabbat to kill Kiva in his place, only to have it destroyed by the Powerd Ixer. The Rook later resurfaces to commit good deeds in a game to get to heaven, found by Megumi as she eventually kills him by targeting the weak point her mother made on him.
 * Lion Fangire (ライオンファンガイア)
 * Statistics
 * True Name: The Creation of Heaven and Earth. Listening to the Baby's Cry and the Angry Roar (天地開闢. 産声と怒号を聞きながら)
 * Tribe: Beast Class
 * Human Form: Rook (ルーク)
 * Actor: Tomohide Takahara (高原 知秀)
 * Episodes: 11, 15-16, 19-20, 25-26, 29-31, Finale
 * Destroyed by: 2008 Ixa's Ixa Judgement

Pearlshell (Mio)
As successor to Maya, the previous Queen, Mio assumes a blue-colored version of her predecessor's Fangire form after she is given an anklet by the Bishop and meets her predestined consort, Taiga. As the new Pearlshell Fangire, Mio can generate several pearls that act as an extension of her will in attacking her enemies. In the end, she is executed by the Bishop after being wounded by Kiva Emperor Form's Emperor Moon Break, dying in Wataru's arms before she shatters.
 * Pearlshell Fangire (パールシェルファンガイア)
 * Statistics
 * True Name: A Dress like an Isolation Cell (独房のようなドレス)
 * Tribe: Aqua Class
 * Human Form: Mio Suzuki (鈴木 深央)
 * Actor: Yuria Haga (芳賀 優里亜)
 * Episodes: 31-43

Pearlshell (Maya)
The second of the original Checkmate Four to appear in the series, pinkish in color, she can generate several pearls that act as an extension of her will in attacking her enemies. She first assumes her form when attacked by Dogga. She assumed this form many times until King stripped away her powers.
 * Pearlshell Fangire (パールシェルファンガイア)
 * Statistics
 * True Name: The Blood Relatives of the Grim Nüwa (冷厳なる女鍋の血族)
 * Tribe: Aqua Class
 * Human Form: Maya (真夜)
 * Actor: Saki Kagami (加賀美 早紀)
 * Episodes: 32-44

Swallowtail
The Bishop of the Checkmate Four is the third member of the Checkmate Four to appear in the series, revealing his true form as the Swallowtail Fangire to both Wataru and Nago in 2008. In this form, he can spray powder, wield a sword and can also dissolve into powder by means of escaping. Most of the time he was the opponent to Ixa, having defeated him in several occasions until at the end, he is finally destroyed by Rising Ixa but before the Bishop dies, he uses his own soul to complete the resurrection of the revived Bat Fangire.
 * Swallowtail Fangire (スワローテイルファンガイア)
 * Statistics
 * True Name: The Ascetic and a Left Foot Sock (禁欲家と左足だけの靴下)
 * Tribe: Insect Class
 * Human Form: Bishop (ビショップ)
 * Actor: Mitsu Murata (村田 充)
 * Episodes: 34-Finale
 * Destroyed by: Rising Ixa's Ixa Judgement

Bat
The Bat Fangire is the true form of the previous King of the Checkmate Four in 1986, usually assuming this form when he cannot transform into Dark Kiva. But after Otoya assumes the mantle of Kiva, King assumes his Fangire form to battle him. In the end, the King is severely weakened by the teamwork of both Kiva and Dark Kiva and has his title transferred to the young Taiga after the infant indirectly kills him by deflecting his attack, also saving Maya's life.
 * Bat Fangire (バットファンガイア)
 * Statistics
 * True Name: The Dawn Sleeps, A Magnificent Story's Ending (暁が眠る、素晴らしき物語の果て)
 * Tribe: Beast Class
 * Human Form: King (キング)
 * Actor: Shinya Niiro (新納 慎也)
 * Episodes: 45-46, 47-Finale
 * Destroyed by: Kiva Emperor Form's and Dark Kiva's Snaking Death-Break/Emperor Moon Break Combo (revived)

In the present day, Bishop manages to resurrect the previous King, though in a more demonic version of his Fangire form without a conscious mind who is motivated to kill those bearing his title. Although the Bat Fangire had overpowered both Kiva and Dark Kiva, the two Riders successfully destroyed him by teamwork.