What are some similarity between how the Inca's and Aztecs were captured?

I do not so an awful lot bout native American history, but I know that the New World in general was devastated by disease, especially smallpox, brought over by the invaders, so I expect both civilzations were very weakened by this. The Aztec empire was defeated by Hernan Cortes who tricked the last emperor or king and had him murdered...Of course, as always, I expect the tactics of missionaries played an important role in their downfall and submission too...