The ant carton consists of particles of wood, dry vegetable material, and soil glued together with sugary secretions collected by the ants from aphids and other homopteran insects (bugs that pierce plant tissues and suck out the sap).
The fungal mycelium (loose network of delicate filaments hyphae or threadlike filaments that form the body of a fungus) grows through the walls of the carton which are strengthened by the symbiotic fungus which reinforces them in the same way that steel mesh or rods reinforce the walls of buildings.
Cleptobiosis is a widespread form of competitive exploitation in ants known as "robbing food" or "stealing food".
The architecture of the mound is often elaborate, specific in plan to the species, and evidently adapted to contribute to microclimate control within the dwelling place.
It is possible that the nest odor is the same as the "colony odor" in some cases. The nest odor of honey bees is often referred to as the "hive aura" or "hive odor".