Police Spies
To gain the upper hand, Nazis used police spies to access information otherwise inaccessible. Police spies became particularly useful when Hitler wanted to stop anti-Nazi propaganda from happening before any had even been created. He did this by hiring Police spies from groups like the SS to seek out and kill anyone likely of producing anti-Nazi material, so that they would either be in jail or dead before they could create propaganda opposing Hitler's rule. Hitler's use of spies shares connections with the character Moses in Animal Farm. The raven, Moses, is Mr. Jones's loyal pet. Moses spies on the other animals for Mr. Jones, and just like the Nazis using spies to protect against anti-Nazi propaganda, Moses spies to protect the farm from pro-Animalism propaganda, hoping to prevent a revolution. The Nazis' use of spies was not as effective for gaining power, but it aided in maintaining Nazi power, because it was more difficult for people to speak out against Hitler.
Genocide
Once Hitler had full control of Germany, he began using eugenics to continue the "pure" Aryan race, and hopefully abolish the other "impure" races or groups, the most famous example being the Jews. Hitler set up concentration camps where massive amounts of people were brought to, tortured, and killed. These camps showed the true state of terror that Germany was really in. It was clear that the goal of these camps was solely execution, as pictures of the concentration camps reveal heaps of dead bodies ready to be moved and discarded by the Nazis. Although these camps were extremely brutal, the core idea of these can connect back to the slaughtering of the hens in Animal Farm. When Hitler decided to start executing large numbers of people, he was doing it because that is what his ideology believed. To Hitler, he was killing the Jews because their existence was going against his idea of the perfect human. In Animal Farm, Napoleon kills the hens because their refusal of giving up the eggs goes against Napoleon's wishes. The ease at which Napoleon and Hitler kill civilians shows their true abuse of power.