"lightning" is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3.0 of the license, or (at your option) any later version.

Authors of textures

lightning_1.png
lightning_2.png
lightning_3.png

Authors of sounds

thunder.1.ogg - CC-BY-SA - hantorio - http://www.freesound.org/people/hantorio/sounds/121945/
thunder.2.ogg - CC-BY-SA - juskiddink - http://www.freesound.org/people/juskiddink/sounds/101948/
thunder.3.ogg - CC-BY-SA - IllusiaProductions - http://www.freesound.org/people/IllusiaProductions/sounds/249950/