Yabun and Naito were once known as James and Brian Williams. The two wished to become famous in any way possible, and Brian thought that if they gained super-human abilities in some way, they could become famous by being the greatest Heroes in Paragon City. James liked the idea, but thought they they should become villains instead due to the wealth they would gain from it. At first Brian was against this, but James promised that they would use the money to get their family out of dept.
They both began searching for ways to become super-villains. They weren't smart enough to use advanced technology, they were afraid of jumping into toxic waste, and they couldn't find any artifacts they granted them abilities. After a while, Brian gave up the attempt to gain powers and began focusing more on his school work. James however continued his search and discovered an ancient piece of Shade Literature that teaches the user how to control shadows. Thinking that he'd found what he'd been searching for, James called Brian and demanded him to come home.
When Brian stepped through the door, he found James being dragged into the darkness of his from by a swarm of black tendrils. When he tried to save his brother, Brian was also consumed, and they both became Umbrals. They were soon found by Kagai and joined The Children of Darkness after Kagai offered them fame and fortune.
Although both Yabun and Naito are Aqua-Kinetic, they also have their own individual abilities. They are both Level 3 Beings, but when working together they are more then a match for a Level 5 being.
- Aqua-Kinesis: Both Yabun and Naito are able to control the forces of water
- Water Creation: Yabun has the ability to create water to control.
- Changing Matter Type: Naito has the ability to change water into its other forms (Vapor, Water, Ice)
- High-Speed Regeneration: Being Umbrals, the twins have to power of regeneration.