Finished going through spoils, returning in intoxicated state (6)
I believe the answer is:
stupor
'intoxicated state' is the definition.
(I've seen this in another clue)
'finished going through spoils returning' is the wordplay.
'finished' becomes 'up' (eg 'time's up' means the time is finished).
'going through' indicates putting letters inside.
'spoils' becomes 'rots' (I've seen this in another clue).
'returning' says the letters should be written in reverse.
'rots' reversed gives 'stor'.
'up' put within 'stor' is 'STUPOR'.
'in' is the link.
(Other definitions for stupor that I've seen before include "state of somnolence" , "state of unawareness" , "Dazed or unconscious condition, sometimes caused by alcohol" , "Marginal consciousness" , "State of dazedness or bemusement" .)