User blog comment:Fimber/Nine questions about "The Wicked Day"/@comment-4135736-20120625091758/@comment-4135736-20120626161636

Merlin has always had a darker side in his personality, in Series 1 rather than accept that Gaius sacrificed himself to save his mother, he just went crazy and killed Nimueh and she even said that she only took his life because Gaius chose to die. In Series 2, rather than tell Morgana the truth that she was the source of the sleeping enchantment, he just coldly poisoned her when she could have accepted the truth and drunk the poison herself, not to mention that he didn't help her with her magic himself and reveal himself to her when she was terrified. Also in Series 3, especially when Morgana's ankle was injured, he just treated her hashly and didn't seem to care that his coldness was the reason why she became evil (he even laughed at one point when Arthur carried the injured Morgana). It wasn't just in Series 4 when he was cold and selfish, he always had that dark side.