Greek character died in sludge (3)
I believe the answer is:
mud
'sludge' is the definition.
(I've seen this in another clue)
'greek character died' is the wordplay.
'greek character' becomes 'mu' (letter from the Greek alphabet).
'died' becomes 'd' (abbreviation next to the year of someone's death).
'mu'+'d'='MUD'
'in' acts as a link.
(Other definitions for mud that I've seen before include "Muck - actionable remarks" , "Clay" , "Soft sticky earth" , "Offensive remarks" , "in your eye, it's an affable toast" .)