Music:
https://www.youtube.com/watch?v=C_5fMEe3bDw
https://www.youtube.com/watch?v=NY1y-0ZD0Rs
http://multi8it.blogspot.com

Sounds:
jalastram - http://opengameart.org/content/8-bit-explosions-free-sound-effects-1

Spaceship Art by: Skorpio
http://opengameart.org/content/space-ship-construction-kit
Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)- https://creativecommons.org/licenses/by-sa/3.0/
GPLv3 - http://www.gnu.org/licenses/gpl-3.0.txt


PowerUp Art by: chabull
http://opengameart.org/content/pickups-powerups
https://creativecommons.org/licenses/by/3.0/