"Ever since you were an apprentice, you've wanted power"
I often make fun of WC for having a bunch of "Born Evil" characters as hyperbole, but in more modern arcs this language usually looks more like "Born With A Seed of Darkness." This idea that some people are born with the "capacity" for evil which others are simply not.
Darktail is an example, Ashfur had the Evil Seed retconned into him, now it seems Splashtail is getting it too.