Mulch Diggums is a fictional kleptomaniac dwarf from the Artemis Fowl series by Irish fiction author Eoin Colfer. He has been arrested numerous times by the LEP due to his criminal nature; stealing from humans and fairies is his speciality. An expert burglar, he is also infamous for his powerful and deadly flatulence, varieties including, the "torpedo", and the "cyclone". As a dwarf, he can tunnel underground using his unhinged jaws at high speeds. He even has his own tools to work in his favor. His beard hair act as antennae and he can pick up vibrations through walls and underground. Also, when they are pulled, they stiffen and form to work as keys and other useful items. When his spit dries it becomes rock solid and glows in the dark. It also contains a sedative. His dwarf rock polish is used to melt glass and metal. A side effect of his flatulence is the buildup of Methanobrevibacter smithii archaea, which prevents aeroembolism. (In reality, the methanobrevibacter smithii is an archaeon found in human guts which helps decompose refined sugars.)

A running joke in the series is that he smells horrible.