Sea sweeping back over cold Greek hero (8)
I believe the answer is:
achilles
'greek hero' is the definition.
(I've seen this before)
'sea sweeping back over cold' is the wordplay.
I cannot really see how this works, but
'cold' could be 'chill' (chill can mean cold) and 'chill' is located in the answer.
an anagram of 'sea' is 'aes' which is located in the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for achilles that I've seen before include "man with a particular weakness" , "Ancient Greek with weak heel" , "Mythical hero, vulnerable only through his heel" , "great hero" , "7 Calf/heel connector" .)