Mundgi Ironbrow is the youngest son of Undgi Ironbrow, owner of the Ruddy Nose Brewery. He was born after the migration of his family from Erebor to Ered Luin, and has grown up in the Low Lands surrounding the fortress of Gondamon.

Mundgi was unfortunate enough to fall off the battlements as an adventurous beardling and cracked his skull, leaving him severely brain-damaged. He is exceptionally large and strong, even for a Dwarf, and the combination of brawniness and an unstable brain has proved itself a dangerous combination. Mundgi often runs off barefoot with only a mining hammer as a weapon in search of 'hidden treasure' or 'adventure', and his family spends a considerable amount of time looking for him and dragging him back home.

The Ironbrows are a very well-off and respected family, so Mundgi can be quite a problem for their image. To help this, Undgi managed to work out a deal with the Bearded Bear Brewery owners to have Mundgi run the brewery (mostly as a de facto position, as he is not capable of running anything), which has given the illusion that Mundgi has a level of status.