The Athonian Tunnel Rats are the regiments of the Imperial Guard that hail from the world of Athonos. This planet's governance is constantly vied for by a dozen rival noble families. The resultant gang warfare amongst their various supporters is brutal and unending, the violence spilling into the streets and sewers of the hydroponic gardens that cover much of Athonos. Such is the recruiting ground for the Athonian Tunnel Rats -- masters of urban combat and amongst the most determined of close-quarter fighters in the Imperial Guard.
- Warhammer 40,000: Rulebook (5th Edition), pg. 141