Survival in the Deep Sea: I Can Graft Anything

[Deep-Sea Survival + Cthulhu + Farming + Base Upgrades + Ruthless Protagonist + Not Overpowered] The sun goes dark, and the surface of the world is locked in eternal ice. The last remnants of humanity flee into the deep sea, migrating between geothermal “oases” on the ocean floor. Lu Yuan, who struggled to survive in his previous life, returns to the beginning of the apocalypse and awakens the [God-Tier Grafting] System. An ordinary sonar conch grafted with [Echo Coral] evolves into a “mental detection field” with an extraordinary range. A shabby one-person submarine grafted with [Pressure Archaea] evolves into an “Abyssal Fortress” capable of withstanding pressure at depths of ten thousand meters. While other survivors despair over a single serving of synthetic protein, bioluminescent algae in Lu Yuan's mobile base already provide self-sustaining energy, and its ecological fish tanks supply a steady source of food. But the true horror lurks in the ten-thousand-meter abyss: the “Tide of Lightlessness” that devours all light and reason. Pollution, mutation, madness... The monsters carried by the tides cannot be killed with conventional weapons. Only those with extraordinary powers who heed the “Echoes of the Old Ones” can kindle a faint glimmer in the dark depths. Hundreds of mysterious deep-sea authorities, hundreds of strange ancient relics...