Public domain drawings of cockroaches from "Histoire physique, naturelle, et politique de Madagascar" via Wikimedia Commons.

https://www.archive.org/stream/histoirephysiquept23pt1gran#page/n277/mode/2up
https://fr.wikipedia.org/wiki/Projet:Biologie/Illustrations/Insectes/Histoire_physique,_naturelle,_et_politique_de_Madagascar

The placeholder tile images floor.png and cwall.png are from the public domain
roguelike tileset "RLTiles". You can find the original tileset at:
http://rltiles.sf.net

Wall and floor tiles:
https://commons.wikimedia.org/wiki/File:Concrete_aggregate_grinding.JPG
https://commons.wikimedia.org/wiki/File:Concrete_Casting_Defect_Blowhole.jpg

Font used in graphics is "Epilog" by Divide By Zero:
http://fonts.tom7.com/

Gun:
https://commons.wikimedia.org/wiki/File:Indumil-Cordova.jpg

Crowbar:
https://commons.wikimedia.org/wiki/File:Standard_Crowbar_Black.jpg