"The Parademons... They are fierceless beasts, who only hung for power. They don't live in anyplace, just consuming the planets that they pass, beasts of death!"
"Our army grew hungry..."
"They hunger will be soon satisfied in the following battle!"
"Why fight against the scum of Earth?They don't need such honor!"
"It will not be an problem, if your army is ruthless as you say..."
The Parademons are a cybernetic alien race subservient of the overlord Darkseid, whom reside in the Netherworld, an gate to Apokolips.
The Parademons are a powerful, technologically advanced race of cyborg-like creatures, and serve Darkseid. When the warlord allied himself with the exiled Ares, the Parademons were granted to him as his personal army to conquer Earth and gain the Ultimate Stone.
Once having gained the Stone from the World Security Council Ares was able to open a portal to the Parademon fleet standing by, thanks to the help of a brainwashed Leonid Pavel. The Parademons immediately started to wreck havoc on Metropolis, destroying buildings and gunning down civilians in the streets. The National Guard was unable to quickly deploy enough troops to counter the invasion. Luckily, the Justice League arrived, having fought Ares repeatedly in an attempt to hinder his efforts at summoning the Parademons. Soon after their arrival, a major battle ensued between them and the Parademons.
Not expecting such a resistance, the Parademons were initially overwhelmed, but soon their numbers increased so much that the superheroes found some difficulties in containing them. Batman took command of the Justice League as well as the police forces, and thanks to his command, the Justice League' powers were properly used as well as displayed while they fought the menace. Eventually, the Secret Party of the World Security Council attempted to blow up the City Center with an kriptonite-prototype bomb in order to contain the Parademon invasion, but Superman intercepted the bomb and disposed of it into the portal, where it impacted and obliterated the Parademon mother ship, instantaneously disabling all Parademon forces on Earth, thus ending the invasion.
After their defeat, pieces of Parademon technology were recovered by both World Security Council, and secretly the terrorist organization Cadmus Labs.
The Parademons are a powerful warrior race, a hybrid between organic beings and machines. They're controlled by a Mother Ship which never shows on the battlefield, and acts as one during war. They have superhuman physical attributes, superior strategy, energy-based rifles, jetpacks and flying vehicles, but their main strength is their almost infinite number of soldiers in combat.