Monumental
Atticus didn't have to be told. He knew exactly the kind of person he was.
He was cold, brutal, and at the same time loving. He could kill without hesitation and at the same time save lives.
There was no way one action or behavior could define a person. People were capable of changing depending on the situation.
But ever since Atticus had gotten reincarnated into this world, he hadn't had any major change in his main temperament or behavior. He had learned from a lot of situations, lessons that he had no plans of forgetting.
But learning was different from behavioral change. It just means that he wouldn't make the same stupid mistakes he made in the past.
However, Atticus's main temperaments remained unchanged. Who he was deep inside.
Atticus was a very vengeful person. He was the sort of person who would go to the ends of the world just to have his revenge. This behavior remained true.