The conquistadors were catholic. They were utterly horrified by what they discovered. Those men were Heroes. Cortez, the Journey of Cabeza de Vaca, Coronado, and I forget his name but the Catholic priest who established the missions in California. Those men were so far from home in terms of time and distance, they may as well have been on Mars. The Bravery they showed leaves me shaking my head
They thought the Aztec's gods were demons--- because they actually were.
All their neighboring tribes--- whom the Aztecs regularly harvested for captives in the "Flower Wars" --- saw it as a horror as well, even if they participated (were forced to, on the Aztecs' terms.) The Tlaxcala, (and to an extent, the Cholula and Huejotzingo) finally had their revenge by allying with the Spanish against Montezuma.
If the Spanish hadn't stopped Montezuma, he would have depopulated the Valley of Mexico.
Whatever you did, remember to have not lost an Incan basketball game.