There is a ton of variation in spelling of names of various Inca rulers. I tried to cover all the spelling variations that I could find, but please tell me if I missed any.
Going back to this quiz I am thinking of adding Paullo Inka and Tupac Hualpa to the list. Even if they were spanish puppet rulers with no actual power, they were officially given the title of Sapa Inka. I think that might be enough to include them, particularly as Manco Capac II started out as a spanish puppet who ended up rebelling to found a rump Inca Empire out of the fringes still not under spanish control.
Not including Ninan Cuyochi as it is not clear if he ever succeeded his father. They were both dying of smallpox, and it is not clear if he lived long enough to be theoretical Sapa Inka for a few days or if Huayana Capac was still alive when his son died but did not have the chance to name a new heir before dying himself. Either way, I doubt Ninan Cuyochi had any chance to actually rule. The death of the Sapa Inca and his chosen heir set off the Inca Civil War, and the arrival of the Spanish in the tail end of the war was the empires downfall.
Not including Ninan Cuyochi as it is not clear if he ever succeeded his father. They were both dying of smallpox, and it is not clear if he lived long enough to be theoretical Sapa Inka for a few days or if Huayana Capac was still alive when his son died but did not have the chance to name a new heir before dying himself. Either way, I doubt Ninan Cuyochi had any chance to actually rule. The death of the Sapa Inca and his chosen heir set off the Inca Civil War, and the arrival of the Spanish in the tail end of the war was the empires downfall.