Introduce your antagonist with as much sympathy as possible
Elliot Teza is a tired old man.
He saw the City transform from its chaotic maze-like roads, built haphazardly over centuries, into the efficient network, populated not by self contained polluting bombs but by clean, autonomous driven vehicles. He saw derelict buildings give way to heave’s defying towers, he saw the same towers, dark and ugly, transform into a spectacle of light and colour, tailored to each singular inhabitant of the City. Over the years, he saw many and more.
But he also saw the love of his life die young, the worry and fear in her eyes in the final years, the resignation and sadness in the final weeks. Together they fought against decease and malady. Together they transformed the world, giving all they had, so everyone could have a second chance in life when the end was sudden. And he saw that same freedom become fenced by those of means. For he saw, when the child of his love by another grew into a fine woman herself, a woman that found happiness in life, a life that ended in one of the last accidents to ever occur. And Elliot Teza, the man who freely give his knowledge so others could prospect, was unable to use it, to restore the daughter of his love back to live.
He was powerless then. But Elliot Teza is powerless no more. He saw to it that the hoarded knowledge bleed back into society, so all could benefit of it. Just old age remains, but even that, is nearly in his grasp. He knows it, he can feel it. And he knows, when death is finally beaten, so to will be the riddle to stops him from bring the daughter of his love back to life, restore her as she was before the accident.
And restore his love as she was, before she gave up.