Breaking Bad's Walter White is one of the most villainous characters in television history, but Better Call Saul's version of the character was equally nefarious and despicable as the infamous Heisenberg. One of Better Call Saul's greatest claims to fame is its well-written and engaging characters, who were just as complex as many of the characters introduced in its sequel series, Breaking Bad. Moreover, the show excelled at exposing audiences to completely different sides of characters who either made appearances in or were featured heavily in Breaking Bad. Perhaps the strongest example of this is Better Call Saul's protagonist, Saul Goodman.

https://screenrant.com/better-call-saul-walter-white-chuck-mcgill-similarities/