Pitiful epic that failed (8)
I believe the answer is:
pathetic
'pitiful' is the definition.
(I know that pitiful can be written as pathetic)
'epic that failed' is the wordplay.
'failed' indicates an anagram.
'epic'+'that'='epicthat'
'epicthat' with letters rearranged gives 'PATHETIC'.
(Other definitions for pathetic that I've seen before include "Pitiable - paltry - touching" , "arousing contempt" , "Contemptible" , "Poignant or hopelessly inadequate" , "Derisory" .)