Shovel Knight creators just released all the assets under Creative Commons:

https://www.kickstarter.com/projects/yachtclubgames/mina-the-hollower/posts/3442745

here's the download

https://mega.nz/file/CO4kARSD#_CEMLfYAZ90Fy7y_VuzZvpZ6Qlc9fQA0UlePtmJe9Vw