Rinnegan easily, i mean it gives you ability to learn EVERY jutsu and EVERY element
Sharingan. I'd kill my family for the Mangekyo. Give up one of my Eyes to a family member that I've spared. Kill him, force someone to Transplant the Mangekyo back, and bang EMS. Then I'd unlock Rinnegan xd

Sharingan. I'd kill my family for the Mangekyo. Give up one of my Eyes to a family member that I've spared. Kill him, force someone to Transplant the Mangekyo back, and bang EMS. Then I'd unlock Rinnegan xd