Throughout his long and arduous studies of the cosmos through his conquests New god of evil; Darksied came across a Martian textile that indicated the presence of a mathematical formula dictating the Life Equation, once he had learned from Martian philosophy that free will and spiritual purpose was defined by such a concept he eventually contemplated that an opposite equation exists too.
The Life Equation is the counterpart of the Anti-Life Equation which allows the wielder to control all sentient life in any universe by mathematically proving life and freewill to be meaningless; on the basis that if someone possesses absolute control over you - you're not really alive. Which means the reverse must hold true through this cosmological formula that proves life is worth living. For unlike the Anti-Life Equation, this one has the power to shift a free thinking individual towards it's users mindset without ripping away their core personage.
With it one not only as the power to not only alienate and alternate freewill but are also able to change the very dictation of all reality as a whole by changing the equation's formula. It, much like that of his Brother Darkseid; has been the lifelong obsession of Izaya in his war against him seeking to use it as a means of tipping the balance of power in his own favor.
Very little too nothing is known for certainty of the Life Equation except that it was somehow related to a secret of the source and co-related to the the various lantern corps symbolism's including the very Seven Lights of the Emotional Spectrum with which they draw their power from;
Will, Rage, Greed, Fear, Compassion, Hope and Love including the core whole which represents the conglomerate of the very essence of life and sentience in a universe.
each a fragment of which coupled with the whole in itself all somehow pertaining to the elusive formula's entirety.
Some 300 years or so ago in the New Earth Universe, Darkseid took a pilgrimage to the Martian home world of Mars, discovering within their ancient texts that Martian philosophy was based on the fact of the Equation's Existence. It was here at that very moment that the god of evil discerned there was an Anti-Life Equation and had spent countless eons searching for it, lusting after total and complete dominance of freewill as a whole.
A wounded and bewildered second Mister Miracle had been found stumbling across an empty sidewalk where he came across a crippled elderly in the street. The wise old soul informed him that because he was able to resist the poisonous Anti-Life's bane that there does exist a Life Equation and that he is somehow connected to it for one good man can make a difference.
Highfather of New Genesis Sought out this formula of great power in his war effort against the tyrannical mad god and brother of the same blood Darkseid. He came to have a fascination with the singular Prime Earth Universe where the despot first made his claim that was quick to reject and repulse him in such a manor, a feat not even Izaya nor all his armies of New Genesis could accomplish in the Eons old struggle they and Apokolips have had just barely managing a stalemate.
The Life Equation was unlocked by Kyle Rayner after he mastered all the rings of the Emotional Spectrum and became a White Lantern.
An alternate universe Darkseid discovered after centuries of searching however his soul was too corrupted to use it. On his moment death he passed it on to Wonder Woman. After Amazo II used the Anti Live Equation to destroy the multiverse, Wonder Woman with the aid of Martian Manhunter and Batman used it to restore creation.
On Earth 55 Darkseid accidently released a corrupted Anti Life Equation onto the universe turning all those infected to Anti-Living Zombies. Neither alive nor dead, the Anti-Living are driven solely by their desire to spread more "anti-life" by either killing or infecting any living thing they can find. Years later the remaining heroes of Earth was able to concoct a cure using the Life Equation.
When the remaining heroes/villains travelled to Limbo to confront Erebus, the source of corruption. Damian Wayne sacrificed himself using the Life Equation to defeat Erebus. The Anti Life Equation and Life Equation collided destroying Erebus' Limbo Dimension then recreating a new universe in the process.