This creature appeared for the first time in the first season finale of the AH.com series.
Although the origin is unknown and the size of the creature is questionable, the consensus is that it's been around for a long time and that it is huge. Psychomeltdown believes it to be a massive robotic ship that was programmed long ago in some forgotten war.
Ward and Doctor What, in the days they were still apart of the Human Unity, met the creature when it attacked a colony of the Human Unity. Then Admiral Ward engaged the creature with the Unity Fleet, but the creature destroyed everything, including the planet. Ward and Doctor What barely survived in their respective ship.
The Devourer since then continued to go about the multiverse, destroying worlds. The reasoning behind it's eradication of worlds inhabited by people is unknown, food, fuel, programming? No one has ever received so much as a warning as to its intention.
When the Devourer attacked a TL that Ward was in the process of conquering for his own pleasure, it spelled the end of the creature. Ward contacted his allies and the AH.com ship, arming them with Molecular Disruptor Devices, they managed to successfully destroy the Devourer of Worlds.
The Devourer of Worlds launches out spherical fighter ships to take care of long range denfeses and vessels of whatever TL it attacks.
It has several powerful close in weapons that can devastate most vessels with a single shot, similar to the CF.net's main cannon.