Aqua Noir is the water upgraded version of the superhero Cat Noir with extra water powers, a  suit with fins on his feet and making him able to breathe and to speak underwater. With the Cat Miraculous, when inhabited by Aqua Plagg, Adrien Agreste secretly transforms into the Aqua Noir, gaining the power of destruction to stop Hawk Moth/Shadow Moth/Monarch and his akumatized villains. He has a staff as a weapon. He only becomes Aqua Noir when there’s a specific villain, like Syren.