Descending adverbs are provided in this article. The words listed here are commonly found along with the verb descending in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb DESCENDING.
abruptly, constantly, continually, directly
finally, gently, gradually, nearly
obliquely, quickly, rapidly, slightly
slowly, steadily, steeply, suddenly
swiftly, vertically
Hope this word list had the descending adverb you were looking for. In addition to adverbs used with descending, other example verb adverb pairings can be found on this site.
You can help by adding more adverbs in the comments. Thanks.