The Beast Planet arrives from the very heart of the Cluster's sun.
The Beast Planet is a space station of incredible size, larger than all significant solid solar bodies including worlds such as Tek and Fire. Its origin is unknown, as is its true purpose as it travels around the universe consuming planets, earning it the name Eater of Worlds.
Its surface is comprised of a seemingly invincible metal armor many tens, or even hundreds, of kilometers thick, and inscribed with unusual markings. It is perfectly spherical aside from its front, which resembles a smaller, recessed sphere, giving an appearance more similar to the shape of an eyeball. This frontal section is able to open fully along a massive central join, revealing a huge detached claw that is able to reach out and grip the surface of a victim world, pulling it inside. A series of smaller openings exist on the sides of the structure, indistinct from the main surface until opened, these contains a set of massive Null Energy Cannons, more powerful even than those found upon the battle-station constructed within Remora.
Within the Beast Planet, and visible through any open surface is a sinister red light, that also appears to be include some form of mist, preventing a clear view of the interior of the structure, and likely produced by a source of Null Energy. The surface displays no visible means of propulsion, and unlike other ships able to travel through rifts in space, it is shown to emerge from stars, through some unknown mechanism.
The Beast Planet is able to create Beast Drones, that it is able to dispatch in order to find suitable worlds and ensure that they are defenseless ahead of its arrival, using more advanced drones such as Blokk and Lamprey to command these forces. The drones able to speak refer to their master simply as "The Beast", and suggest that it possesses some intelligence, as they fear invoking its displeasure by failing in their mission.
Who created the Beast Planet is never revealed, though its technology is demonstrably superior in every way to that of the advanced planet Tek, and the planets comprising the Cluster. It is possible that it is a remnant of a highly advanced race, such as that which created the World Engines. The purpose and nature of the processes through which the Beast Planet consumes world is unknown, as it appears capable of consuming only the interior of a world, leaving its crust intact, with the core replaced by Null Energy.
The Beast Planet is first seen in Episode 1.1 "Behold the Beast" as it attacks and destroys planet Tek which, in desperation, sends Tekla away in a small fighter craft in the hopes that one of their race might survive the slaughter.
The Beast Planet then makes a Flashback appearance on Episode 1.9 "Rock & Ruin", when the Alliance makes a last ditch effort to bring Planet Rock into the Alliance by showing Lord Mantel evidence of the Beast destroying Planet Water and its utter invulnerability against Water's planetary-size weapons.
In Episode 2.1 "War within Worlds" the beleaguered forces of the Cluster attempt to rally a defense against the fearsome new menace as it fires at the already weary fleet, trivially destroying one of planet Rock's Battle Moons. When a second shot seems certain to destroy planet Ice, Tekla, manages to find and activate the planet's mysterious hidden World Engine in time to move the world out of harm's way.
The events of Episode 2.2 "This is the Way the World Ends…" focuses upon the attempts to locate and activate planet Fire's badly damaged World Engine. However, the population is forced to evacuate when it becomes clear that the world's engines are too weak for the planet to escape. The Vizier of Fire, in a display of heroism, offers to stay on the doomed world, and directs the World Engine to crash into the Beast Planet's grasping claw.
During Episode 2.7 "Timebomb", after discovering a seemingly uninhabited world, the Alliance make a decision to set a trap for the Beast by rigging the Planet's (Jungle) world engines with explosives in an effort to destroy the Beast inside its Shell.
In their exploration of the planet, and with the help of Zuma, they discover that all the Planet's plant-life is a sentient being, but that its World Engines are damaged beyond repair, forcing Planet Jungle to agree to the ultimate sacrifice.
The Beast Planet arrives and grips the Planet with its World Claw grasping it inside. When Jungle explodes inside the Beast Planet it is revealed the Beast is not fazed by this explosion.
During Episode 2.12 "The Long Road Home", the Beast Planet is almost upon the precarious allied forces when the Prison Planet returns directly in its path, with Graveheart and the others safely off it, the Prison Planet activates its Teleport Engine as the Beast's claw crashes into its surface, teleporting the entire Beast Planet to a new, unknown location, saving the planets from destruction.