Kyanite is on of the antagonists of the Legend of Onyx series.
Kyanite weres a dark blue cloak similar to a thief's and wears blue robes underneath. He has a set of daggers on the side of him and also carries a money bag with him.
Kyanite is known to be a bit of a mercenary based on the fact Ruby paid him to attack Beach City in the episode, The Storm Gem. He is also shown to be extremely gifted in battle with his powerful weapon attacks and with the powers of controlling weather.
Kyanite's hammer is as powerful as a hurricane when he brings it into battle. The hammer is dark blue with a black handle with a light blue lightning bolt engraved on the side of the hammer. The hammer allows the user to have the power to control weather and use it in combat along with the hammer's strength.