Who was the 9th and greatest Inca ruler?

The 9th and often regarded as the greatest Inca ruler was Pachacuti, who reigned from 1438 to 1471. He is credited with transforming the Inca Empire from a small kingdom into a vast empire through military conquests, administrative reforms, and the establishment of Cusco as its capital. Pachacuti also initiated significant architectural projects, including the construction of Machu Picchu and the expansion of agricultural terraces. His leadership laid the foundation for the Inca Empire's prosperity and influence in South America.