As told by Blackhand, High Usher of the Eternal Night, Priest to the Glory of Mordak, the Last Game.

One time in Heaven, Mighty Yultan and Silent Mordak were intent about their labors, working for the good of all Gods, when they happened to pass through the Hall of Feasts. Intended for the enjoyment of the Lesser Gods, the Twins Eternal had never stopped before to partake of the luxuries and pleasures of the Hall of Feasts. And it was within the Hall when they were waylaid by the God of Chaos, the God of the Alluring manner and the intented of Demons, Byron.

Byron sang a sweet song of temptation, entrapping the First God in his web of deceit. Without understanding what he was doing, the Lordly Yultan has made to swear an Oath not to harm the interests of the DemonLord, nor those of his lackey sidekick, or any of the foul offspring they had sired upon the Earth.

Then the God of Lawyers tricked Yultan and the steely Mordak both into promising to fight one another. Not content with this, the God of Petty Bureaucrats kept the Twins by his side, until they had missed their Time of Duel, which they later realized had shamed them. Lo, it had come to pass that the two foremost defenders of Heaven had been tricked, humbled and degraded by the Prince of Lies, Agent of Demons and Depiser of the True Gods. And Yultan and Mordak swore to bring down the false God Byron, bind Chaos from promoting further harm upon Heaven, and to protect the Lesser Gods from other attacks by Demon Lackeys.