Non Gratus Rodentum (also known as Tunnel Rats) is a solitaire dungeon crawl where you generate and explore Vietcong tunnel mazes during the Vietnam war, rolling dice on the tables provided and drawing an abstract representation of the tunnels to explore, fighting enemies and avoiding traps. The game, that comes as a pdf, can be played as a campaign in three acts, where you explore tunnels of increasing complexity, gaining points to spend on recruits and equipment. Surviving the three acts (for a total of 12 tunnels) means you have survived the war, and you can make it home alive.