I liked it, it's funny we did the same concept but the other way around, where you're actually fighting winter instead of freeing her. Unlike the first commenter I would actually say I thought it was a bit slower than I expected, but it was fun nonetheless.
I have a small nitpick against the music, it did not feel like it really fit the game that well? Something more fast-paced might have felt better.
I quite liked the bosses' designs though, do you plan on making more?