The Prestige movie: questions about Angier's character?

So I have to write this essay about Angier's character development for
school and I need ideas. I'm gonna write about how Angier used to be
"a good guy" at the beginning but at the end he was corrupted. What
else could I say? What are some examples I can use? - an important one
is when he says "I don't care about my wife" to olivia, which shows
that it isnt revenge anymore, but its something bigger. what else?

thanks for all your help