I think hes a bit better in the manga where he starts out being a little evil but stops using his shadow powers to torment those he defeats after finding out about Pegasus' past. In the anime he just went from a dark hero at the start in DK to a normal hero in BC that was suddenly super forgiving, not blaming normal Marik for all that he did to him and his friends once he learned that Yami Marik was the one who killed his father and he had a reason to think the Pharaoh did it. It's a bit strange that the modern day Yami-Yugi (when playing the role of King Atem in the Memory World) behaves basically the same way as his original self, even though he has no memories of his life before being sealed as a soul in the Puzzle.
