He realised something was wrong in the car.
The crash should have killed him with his father, but no; he escaped without a scratch. Then, when the influenza hit his town he remained hale and hearty while everyone coughed and sneezed. Diseases were no longer a worry for him, and he was strong, but this health, this unchanging constitution, felt...wrong.
He used the red lacquer box, tried to contact the New Architect, but there was no answer.
Leaf grew older. He did too, but suddenly, one day, he stopped. They both realised they didn't have much time together, but did their utmost to ignore the glaring fact. However long they did have, it was not enough to be spent in wasted defiance. When Leaf died, he was right next to her, gripping her hand. The nurse thought he was her son.
He decided to end it all. A jump from the top, and he would be free. Free of this cursed existence, for it was not living, nor surviving. No, he wasn't even surviving, was he? He feared he merely was, without effort, without trial. It was a nightmare to behold. Arthur stepped off the ledge.
He was still alive. And Arthur screamed then, for now he knew: He was part of the New Architect, just as the Old One had been. His life, his identity, they were all lies. He cried, begged, pleaded to be released into Nothing.
Blissful silence enveloped him, and Arthur slept.
The New Architect felt a far-off disturbance, a vague unease that in his mortal form would have been crippling guilt and sadness, at the sight of Arthur's suspended form. They were one, yet apart. Arthur was the Architect, but the Architect was more than Arthur, and the world was the Architect's. The desires of his former humanity could not surpass the New Architect's omnipotence. At least, not yet.
Arthur could never die. He could never follow Leaf into Nothing. Nor could he age, and for that, Arthur hated Him and himself. But it was better for Arthur to believe that sleep was the last respite. Let him dream of forever with Leaf, again and again. Time would come when Arthur would realise, when he would achieve clarity even in slumber, and he would revolt, rise up in rage, and break free of his gilded cage. But until then, let him live the life of his dreams, and never wake.
The New Architect wasn't tired yet.