A new trailer for Zack Snyder's Justice League has been released, bringing with it our first proper look at the various League members in action. Batman, Wonder Woman, The Flash, Cyborg and Aquaman each get a moment, highlighting their powers and showing them kicking ass in the name of justice. Of course, there are also some select shots of the various fun crossover scenarios we can expect, such as Aquaman riding the Batmobile and Wonder Woman, Aquaman and The Flash poised to head into battle.

Within all the wham, bang, boom we also get a good look at what the world's finest are up against – parademons. The emphasis is obviously on the big action and spectacle from the heroes' point of view, but the insect-like wings and alien features of the space soldiers can be seen clear as day (right before Aquaman impales them or Batman blows them up, that is). Batman v Superman: Dawn of Justice fans will recognize them immediately as the same creatures that swarmed the Dark Knight during his nightmare of Superman causing the apocalypse, right before The Flash visited him with a foreboding message. Needless to say, the teaser makes it abundantly clear that message and dream both had an element of pertinent truth to them.

But, even with that Dawn of Justice sequence, who or what the parademons are in the DC cinematic universe remains unclear. One can surmise they're not here to serve under a Superman gone rogue, and the shot with the glowing Mother Box early in the footage suggests they've been sent to retrieve it, but for whom and to what end? Let's look to their comic book origins to hopefully shed some light on the alien menace.

What Are They?

Justice League - Aquaman fights parademons

Parademons hail from a planet called Apokolips, first introduced in the New Gods #1 in 1971, written and drawn by Jack Kirby. Apokolips is an ecumenical planet, meaning that it's entirely covered in industrial and urban areas that form one global city. Ruled by Darkseid (more on him in a moment), the planet is a cruel place on which inhabitants both born there and from other planets are subjected to endless cruel torture, in order to break them and turn them into slaves or soldiers. Parademons are essentially the police force who maintain order and stability with exactly the kind of approach you'd expect from a slave planet, and are the military force for Darkseid. Picked from the most maniacal and sociopathic and given mechanical wings and weapons and trained in combat, parademons are a militarized army of flying pests with an intense bloodlust, ready to swarm at the behest of any of their rulers without hesitancy.

They're often accompanied by Hounds (literally giant dogs) when they attack. From the Batman v Superman scene and this trailer, it seems the Hounds may have been re-purposed into hulking parademons, bigger in size and stature with extra armor. Like in Bruce's pseudo-premonition, the demons and their dogs are incredibly dangerous when in high numbers, able to attack and takedown the most resourceful and able of hero in a matter of time. They're designed explicitly to over-power, whether that means with brute strength or sheer numbers. They don't stop until their pathway to earth is closed and their commander is defeated or otherwise somehow dissuaded, making them a gruelling adversary for any opposing force.

Who Is Controlling Them?

Justice League - Amazons fighting parademons

Apokolips is ruled in a strict theocracy by Darkseid, the single monarch of the planet. Darkseid's only goal is to conquer the universe and it was vaguely hinted by Lex Luthor at the end of Batman V Superman that Darkseid was heading to earth. It was confirmed sometime ago that Steppenwolf, an uncle of Darkseid who featured in a deleted Batman v Superman scene, is the main villain of Justice League. Thus, it's fair to say he, or it, will be the acting commander of the parademons' assault on earth.

The first glimpse we get of a parademon in the trailer comes when one of the monsters appears behind Dr. Silas Stone (Cyborg's father), apparently in pursuit of a glowing cube in his possession  – the same cube seen constructing Cyborg in his cameo in Dawn of Justice. The cube is a Mother Box - a supercomputer capable of healing living tissue, among other things technologically far beyond that of human capability. It's a common piece of tech on Apokolips, and however it made its way to earth, Steppenwolf has likely been sent to retrieve it and possibly kidnaps or kills Silas in the process, kicking off the events of the film.

Or it could be that Steppenwolf decides to take back the box, then enslave earth with the parademons. No doubt Darkseid views Earth as easy meat, underestimating the meta-humans and places like Atlantis and Themyscira. The latter can be seen waging war with an entire army of parademons, which could either be the result of Diana calling in reinforcements to help the Justice League, or could be the inciting attack that Wonder Woman refers to in the trailer.

A Darkseid appearance is one of the bigger questions of the movie, and one unlikely to be spoiled by any trailers. With enemies as strong in number and brutal in force as the parademons, the seven will need to unite for the challenge in front of them, and worry about any generals and kings a little later.

Next: 33 Things We Learned on the Set of Justice League

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