The term 'Mountain Dweller' can be summarized by two crossword solutions: IBEX (4 letters) and LLAMA (5 letters). An IBEX is a species of wild mountain goat that is found in the mountainous regions of Europe, North Africa, and Asia. They are known for their large curved horns and sure-footedness on rocky terrain. A LLAMA is a domesticated South American mammal that is used as a pack animal and for its wool. It is closely related to the wild guanaco and is native to the Andes Mountains.