atrociously vs rottenly

atrociously and rottenly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
atrociously	No	No	No	Yes
rottenly	No	No	No	Yes

As adverbs, atrociously and rottenly are synonyms defined as:

Other synonyms of atrociously include abominably, abysmally, awfully, terribly.

atrociously (adverb)	rottenly (adverb)
in a terrible manner	in a terrible manner
to an extravagant or immoderate degree