Violence
Sergio Leone wanted to show the violence of the Old West in a very straightforward way. In order to do so he needed to connect the act of killing with a consequence. Thus, the audience is able to experience the theme in a dramatically different way than what was typically seen in westerns. Examples of the violence include Blondie's trek through the desert and his burnt face, a man being hung from a tree attempting to wriggle himself free, Angel Eyes brutality in inflicting pain on Tuco and beating him, a man being drug underneath a train. All of this violence connects the acts of killing and torture to a real consequence thus creating a feeling far beyond what most audiences had experienced in cinema.
Greed
Throughout the film we see The Good, The Bad and The Ugly in pursuit of one thing: money. At the expense of anything and everyone in their way they seek to gain a larger share solely for themselves. Along the way we see them killing everyone in their path in order to get rich. We watch as Tuco wants to kill Blondie and in the very next breath is his best friend because he holds the information to where the money is buried. We also see Tuco stealing from dead soldiers. It shows that he has no respect for others in who they were, only in what they have and what he can take from them.
As for Angel Eyes, he can be understood as a man who is after only money as well. We see him kill a man that's paid him $500 and takes $1,000 from a dead man after shooting him and taking his son's life as well. And throughout the rest of the film his pursuit is that of the treasure Bill Carson is said to have buried. All of these men care nothing for the Civil War that is happening in the midst of their greedy pursuit. They care only of their gain.
The Cowboy
Sergio Leone's cowboy character is much different than the one people came to know through John Wayne and the films of John Ford. The cowboy isn't the hero in this film, instead he is the antihero. A man that is not out to protect others, but for personal gain. To this point the majority of films had focused exclusively on the point of view of the cowboy gunslinger as the savior of a town and its people. This film reveals that the gunslinger is not a romanticised character. He is someone who is out to take what he wants and instead of ridding a place of violence they are the ones that bring the violence. Thus the antihero is someone that does wrong, but because Leone and the screenwriters took care to build backstories for them, characters such as Tuco are able to be seen as human beings living in a troubled war. The example being the scene between Tuco and his brother who has become a priest. From this we are able to understand how he became the man he is rather than assuming he is just simply bad.
