Mood affected destiny (4)
I believe the answer is:
doom
'destiny' is the definition.
(doom is a kind of destiny)
'mood affected' is the wordplay.
'affected' indicates anagramming the letters.
'mood' is an anagram of 'DOOM'.
(Other definitions for doom that I've seen before include "Condemn (to certain death?)" , "Terrible fate; death" , "Mood for damnation" , "Bad destiny" , "Fate; ruin" .)