The thirteenth member of the legion, summoned by the Legion of the Black Hand, this class-six demonic entity was - with some magical assistance by Marcus Boyce and the Red Panda - banished from the mortal realm by the Flying Squirrel.
Later in The Gathering Storm he is revealed to be the leader of an army of magical lizard people called the draxcytes. In The Darkness Beyond Kit and John visit the world were the Destroyer reigns and learn that the draxcytes are magically bound to the Destroyer and now that he has been captured they are finally free to live their own lives. Unfortunately it is soon reveled that the Destroyers captor is non-other then Professor Friedrich von Schlitz.
It is not until the season finally that we learn von Schlitz designs for the creature. He means to use it's god like power to fuel his Dark Towers. A network of towers the will make an invasion of Germany impossible and Nazi victory inevitable. Even worse once the Destroyer power becomes to powerful to control he will take his revenge on our world. With the help of The Stranger, John Doe and the Squirrel the Panda manages to banish the Destroyer into the realm of dead.