This game powered by Torque Game Builder, aka Torque 2D.
http://garagegames.com/

Graphics are based on Sean Howard's The Free Pixel Project under the Creative Commons BY-NC-SA 3.0 license.

Free Pixel Project: 
http://www.squidi.net/pixel

Creative Commons BY-NC-SA 3.0 license:
http://creativecommons.org/licenses/by-nc-sa/3.0/