https://screenrant.com/smallville-character-rosenbaum-dislike/

Michael Rosenbaum revealed to Tom Welling that he wasn't a big fan of one of Smallville's recurring characters and how they were portrayed.

Smallville's Michael Rosenbaum Didn't Get Along With One Cast Member: 'He Was Weird' (https://www.looper.com/1505344/smallville-michael-rosenbaum-didnt-like-michael-ironside/)

Michael Rosenbaum seems to have gotten along with most cast members during his time portraying Lex Luthor on "Smallville." But one actor butted heads.