WARNING: This article contains spoilers for The Green Lantern #2 by Grant Morrison, Liam Sharp, Steve Oliff and Tom Orzechowski, on sale now.
While the DC Universe is filled with hundreds of alien villains, Controller Mu, DC's newest intergalactic menace, has already put together an impressive list of accomplishments that would make the Justice League's worst enemies jealous. In just two appearances, this powerhouse Green Lantern foe has established himself as a major cosmic player, and he hasn't even gotten his hands dirty yet.
On the last page of Grant Morrison and Liam Sharp's The Green Lantern #1, Mu revealed that he was gathering several objects of power to build an unidentified "ultimate asset." After his surrogates captured a probability-manipulating Luck Dial earlier in that issue, the story ended with Mu extracting the heart of the Weaponeer, an Anti-Matter Lantern. In The Green Lantern #2, Mu took another few steps towards his final goal, and he even helped a group of alien criminals steal the Earth.
At the beginning of this issue, Mu's forces rescue Evil Star, a longtime Green Lantern villain, from his cosmic prison. With his starlight-powered Star-Band, Evil gave himself artificial immortality at the cost of 2.5 billion lives on his homeworld, Auron. While that made him a genocidal killer on a planetary scale, one of Mu's commanders attacks him, steals the Star-Brand and reduces him to a withered husk without breaking a sweat.
Later on in the issue, Mu reveals that he's been using technology from the Star-Brand and his other objects of power to create Exomantle Body Armor. With thought-controlled "maser blasters," super-strength, enhanced speed and force field-creating capabilities, Mu claims that these suits were as strong, if not stronger, than Green Lantern rings, and are already in mass production. Despite the strengths of these suits, it's still not clear if they're Mu's final goal, since he's still gathering additional resources.
After demonstrating the armor's power, Mu reveals the terms of a previously-unmentioned arrangement with Voltar Zo and other aliens from Dhor, the planet once ruled by the Green Lantern villain Kanjar Ro. Under Mu's protection, the Dhorians use a combination of "gravity refractors and dwarf star lens arrays" to steal the Earth.
Before he was called away to interrogate a decrepit Evil Star, Hal Jordan, one of Earth's Green Lanterns, was already investigating the unexplained disappearances of several other worlds that vanished overnight. After realizing that something about this case didn't add up, Hal travels back to the Solar System and finds his homeworld, and its population, missing, with no trace of its existence other than the Moon.
While it's still not clear how, or if, Earth's disappearance figures into his plans, Mu and the other Controllers are one of DC's oldest and most dangerous alien races.
In the modern DC Universe, the immortal Controllers were originally from Maltus, the planet that gave birth to the Guardians of the Universe who formed the Green Lantern Corps. While the Guardians formed the Corps to protect the universe, the Controllers wanted to achieve peace and wipe out evil by eliminating free will.
To help them achieve their ends, the Controllers created the Darkstars, a militaristic intergalactic fighting force. Instead of using the Darkstars, Mu's subordinates are called the Blackstars, which could indicate that he's working independently from any other Controllers.
Even though Mu's final goal still isn't totally clear, Hal Jordan is probably more concerned about Earth's current whereabouts at the moment, which he'll doubtlessly continue investigating in The Green Lantern #3 by Grant Morrison and Liam Sharp, which is set to be released on Jan. 9, 2019.