Dark Lightning Coeos

Dark Lightning Koios (黒雷のコイオス, Kokurai no Koiosu?) is the third Titan Pontos released from Tartarus[38] and Phoebe's consort.[17] Kronos considers him his "greatest killer", but Koios is one of the most caring and gentle Titans. He has a strong sense of loyalty and decorum, much like Hyperion, whom he is very close to.[60] Both give great importance to releasing their human followers.[58] Enemies and friends alike admire him, but despite being the "good guy" among the Titans, Koios enjoys a good fight. He prefers to avoid unnecessary death but he can be lethal and merciless once the enemy decides to fight.[41]

Shortly after being reborn, he challenged Aiolia while the Saint guarded a meditating Shaka.[41] Koios held the upper hand throughout most of the fight, but in the end he had to be saved by Hyperion after Aiolia unleashed his "Photon Burst".[8] The attack irrevocably injured his yet imperfect body, rendering him a mortal.[71]

Koios is very perceptive. He is called "the one who understands everything",[72] and therefore he is the first Titan to realise Pontos's and Mnemosyne's betrayal to their cause and the true potential of humans. He challenges Aiolia a second time in Kronos's Labyrinth with the intention of teaching him to be a perfect warrior, since the Leo Saint's training had never been completed after Aiolos's death. He forces Aiolia to reach his seventh sense, which leads to his defeat. As he is sucked into Tartarus, Aiolia attempts to save him, but Koios accepts his fate and gives the power of "Keraunos" (雷 – ケラウノス, Keraunosu?), the god-killing lightning he had devised in ancient times to end the Titanomachy, to his opponent.[71]

Koios is extremely fast, even for a Gold Saint and, like Aiolia, he can control and use lightning in battle.[72] His Soma has the shape of a rapier when it is not being used.[38]
 * Techniques:
 * - Ebony Illumination (漆黒光源 – エボニー·イルミネイション, Ebonī Irumineishon?)
 * - Sparkle Rapier (閃光刺突 – スパークル·レイピア, Supākuru Reipia?)
 * - Ebony Gale (漆黒疾風 – エボニー·ゲイル, Ebonī Geiru?)
 * - Thunder Black Rotation (雷黒自転, Raikoku Jiden?)
 * - Ebony Rapier (漆黒刺突 – エボニー·レイピア, Ebonī Reipia?)
 * - Ebony Plasma (黒雷放電 – エボニー·プラズマ, Ebonī Purazuma?)