Catachan is the most infamous planet in the multiverse. It is located in the Ultima Segmentum and is covered in dense jungle. The planet's entire ecosystem seems consciously hostile to all foreign life. Each and every element of the native flora and fauna of the planet represents a real danger to any sentinent race. Catachan's only valuable resource is its sentinent races, who by virtue of being born on the harshest world in the Multiverse are invariably tough and cunning. It is home to the renowned Catachan Jungle Fighters regiments of the Alliance of Nations.