Crag adjectives are listed in this post. Each word below can often be found in front of the noun crag in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing CRAG.
beetling, castled, gray
great, grey, high
highest, huge, icy
lofty, overhanging, precipitous
rocky, slippery, steep
Hope this word list had the adjective used with crag you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.