This makes him far more complicated than just a grandfatherly sorcerer because despite his incredible power and loving nature, he is also deeply flawed.
Since the Harry Potter films were mostly through Harry’s eyes, many of Dumbledore’s machinations were hidden from us for much of the story.
As Evanna Lynch notes, in The Half-Blood Prince (and really the end of The Order of the Phoenix and beyond) we begin to learn more about Dumbledore’s plans and what he knew, and it definitely casts the wizard in a different light.
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