How were incan and aztec religious practices similar? how were they different?

The Aztecs and the Inca had simililar Gods, such as the Inca Viracocha and Aztec Quetzalcoatl, and they both believed in ritual sacrifices
Among the differences was that the Inca sacrificed the best of its children, first feeding them to fatten them up. For the Aztec, what was important is that the victim suffered, as they believed that the tears of the sacrificed children were important, and they made their victims suffer to make sure they cried.

He gathered information from primary sources.