Adrian entered the event at the same time that the players got inside of their gaming pods. In fact, he also knew the backstory of his character. What he did not know is that the gods and goddesses of Pandemonium had a different script to that of what is his character.
His character right now is the King of Twilight, Hay-lale. The progenitor god of the beings that controlled light and darkness. In fact, his demise is tragic because he got usurped by the infamous Goddess of Light and the God of Darkness.
He did not think that the two students that he nurtured would be the sole reason of his own undoing. As the universe kept expanding, just having one god that governs over light and darkness has become a burden to the God of Light and Darkness, Hay-lale.
He nurtured two gifted individuals in order to support him in governing light and darkness. The two are none other than Luminaria and Scotus. This was before the time where the dark gods came to Pandemonium.