Farran the Poisoner was a male fox who followed Ferahgo the Assassin's horde, working occasionally as a mercenary. His fur was completely black and his eyes pale amber; it was said he could kill with a long stare. Farran never spoke, only gesturing in response. He often walked on all fours. His sole clothing was an adder-skin belt with pouches made from the skin of bats. He also carried a dagger made from greenhart wood with a poisoned tip. Ferahgo employed Farran to enter Salamandastron and poison the food and water supplies. He assassinated Windpaw in the process, but the mission proved to be successful. However, he had not planned on the poison working so speedily; when the young hare Shorebuck was killed prematurely at the breakfast table, he was discovered and forced to run for his life. Farran was corralled into a lower chamber of the mountain by the hares of Salamandastron's Long Patrol, and was killed there by Urthstripe the Strong soon afterwards with his own poison.
Later, Klitch drank the poisoned water, by which he met his untimely demise while the Guosssom and the Long Patrol hares were celebrating their victory over the Corpsemakers.