Arknights: Another Sarcophagus

[Growing Up, Amnesia, Dogs, Two Opposing Protagonists, Ensemble Cast, and Worldbuilding]

"People have to look forward. Since everything about this story has been a mess, at least let the ending be happy."

At the heart of the story is the "sarcophagus," a device that shapes the conflicts and entanglements between the protagonist, the "Advocate," and the "Doctor" as they grapple with the survival of civilization and the choices of humanity. The Advocate once gave everything for humanity's survival, but during the apocalyptic crisis, he was branded a threat, betrayed, and hunted down. He and the Doctor go from allies to adversaries, eventually choosing to carry out their respective plans through different sarcophagi. The sarcophagus conceals secrets from a previous civilization. It can prolong life, but may also bring about catastrophic change. Meanwhile, the races and factions of Terra are gradually drawn into this struggle over the fate of the world.