Reverb is Xaxon's Sonorosian (a species from the planet Sonorosia) form. He appears as a rather short, paper-white humanoid. His head is an oval shape, with the base having sharp corners creating a shape rather like a sideways D. On each wrist is a small circle, similar to a speaker. His eyes are thin and rectangular and glow green. He seems to have a perpetual frown, which also glows green. When he opens his mouth, it resembles a green speaker. On his back, he has a rectangular prism which appears similar to a power pack. Attached to this pack are two wires which then attach to headphones on each side of his head. There is a line running from his head which divides his body in two on his front and back. It is interrupted on his chest, however, where it intersects with a horizontal line. This line's endpoints are the endpoints of two more lines which form an X, then connect to another horizontal line, out from which the vertical line continues. On each of his ankles there is something resembling a black power outlet. His Protomnitrix Symbol is in the center of the X on his chest.
Reverb can emit powerfully concussive sonic waves as weapons. These waves can even be used to stop projectiles mid-air. He can also sense vibrations in the ground and use echolocation. He can also create innumerable clones of himself. Creating a small army of Reverbs is one of his most common moves.
- An X interrupting a black line is a common occurance on Xaxon's aliens.
- Echo Echo, from Ben 10 Planet - the Ben 10 Resource!