Bio: Shriev was a brilliant sound engineer until Derek Powers
stopped his funding. In order to save his business, Shreiv created a
suit of sound for demolition. Powers saw no real use of it, until he
discovered it could be used to destroy more than blocks. In order to
please Powers, Shriev was assigned to kill Bruce Wayne. As a result, he
became Shriek; a villain with sound based powers. Shreiv is able to use
sound vibrations to create earthquakes and other destructive properties.
He's also able to "mute" all sound in a surrounding area. Able to
transmit radio signals to receivers the size of a paperclip.
After his first encounter with Batman, Shriek's suit was damage, which
caused him to lose all hearing. While he was eventually able to form a
kind of hearing aid, he was never able to fully regain his sound.
For more, refer to the Justice League Unlimited bio.