Promoting a series of operatic works beginning with endless violence (10)

'promoting' is the definition.
(as in promoting or furthering a cause)

'a series of operatic works beginning with endless violence' is the wordplay.
'a series of operatic works' becomes 'TheRing' (the Ring cycle by Richard Wagner).
'beginning with' is a charade indicator (letters next to each other) (some letters go at the beginning of others).
'endless' means to remove the last letter.
'violence' becomes 'fury' (synonyms).
'fury' with its final letter removed is 'fur'.
'thering' put after 'fur' is 'FURTHERING'.