As my friend Natalie on Goodreads said, Prodigy is "leaps and bounds ahead of Legend".
Prodigy, in my opinion, was infinitely better than Legend. First all, the plot has more going on. More action and fight scenes, some political intriugue, some romance, and worldbuilding. And lots of twists and turns. Awesome.
I loved June in this one. In Legend, I was unsure what to think of her, but I definitely like her in Prodigy. She's really intelligent, clever, she stays calm in sticky situations, and she's pretty kickass too. Kind of like Azula from Avatar; the Last Airbender. Only June's not evil. :)
I do like Day, but I feel like he is a bit too angsty in this. It's only near the end that he acts more like the sarcastic, smartass kid we know from Legend.
I'm still unsure how to feel about their romance. I can see they definitely work well together, but I think that their relationship should stay a purely platonic one. That is, if
That ending, though! Such a cliffhanger.(show spoiler)
Overall, a very solid sequel and a definite improvement, IMO. I cannot wait to read Champion!