Needing no introduction, criticises remains (5)
I believe the answer is:
lasts
'remains' is the definition.
(I've seen this in another clue)
'needing no introduction criticises' is the wordplay.
'needing no introduction' means to remove the first letter.
'criticises' becomes 'blasts' (I've seen this in another clue).
'blasts' with its initial letter taken away is 'LASTS'.
(Other definitions for lasts that I've seen before include "Endures" , "Goes on" , "Keeps on" , "carries on" , "Cobblers' tools" .)