marvelously vs superbly

marvelously and superbly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
marvelously	No	No	No	Yes
superbly	No	No	No	Yes

As adverbs, marvelously and superbly are synonyms defined as:

Other synonyms of marvelously include marvellously, terrifically, toppingly, wonderfully, wondrous, wondrously.

marvelously (adverb)	superbly (adverb)
(used as an intensifier) excellently	(used as an intensifier) excellently