Inspired work of one author))) Unfortunately I do not know his name. But the work is very beautiful. I decided to do the same chicken. And excuse me for my english. I write through the Google translator.
Yeah, the license is CC-BY https://creativecommons.org/licenses/by/4.0/ so you just have to add some attribution somewhere in the game: https://wiki.creativecommons.org/wiki/best_practices_for_attribution
Can I use him for a simple game?