1. Absolute Power and Domination: The One Ring grants its wearer immense power, effectively making them the ultimate ruler of Middle-earth. Sauron, being a being of pure evil, would use this power to enslave all living beings and reshape the world in his own twisted image.
2. Unleashing Evil and Destruction: Sauron's goal is to dominate Middle-earth and reshape it in his own image. Gaining the One Ring would allow him to unleash his full power, leading to widespread destruction, suffering, and the enslavement of all free peoples.
3. The Return of Morgoth: The One Ring is connected to the creation of the other Rings and, ultimately, to the original source of power, Morgoth. By regaining the Ring, Sauron would be reunited with its power, essentially making him a "new Morgoth", an even greater threat to the world.
4. Corruption and Loss of Humanity: The Ring has a corrupting influence, twisting the minds and souls of its wearers. Even those with good intentions are susceptible to its corrupting influence, losing their humanity and becoming consumed by its power.
5. Threat to Free Will: Sauron's ultimate goal is to control the world, including its inhabitants, and to force them to submit to his will. The One Ring grants him the power to do so, effectively eliminating free will and turning Middle-earth into a prison.
6. Destruction of All Things Good: With the power of the Ring, Sauron would be able to destroy all that is good and beautiful in the world. The lands of Middle-earth would become barren and desolate, filled with fear and despair.
In essence, Sauron's possession of the One Ring would spell the end of all hope for Middle-earth, leaving only darkness and despair in its wake. The struggle against Sauron is a fight for the very soul of the world, and allowing him to gain the Ring would be a catastrophic defeat for all who value freedom and goodness.