United players criticise book about heroism, surprisingly (9,5)
I believe the answer is:
pantomime horse
'united players' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'criticise book about heroism surprisingly' is the wordplay.
'criticise' becomes 'pan' (informal term meaning to criticise heavily).
'book' becomes 'tome' (a tome is a book).
'about' is an insertion indicator.
'surprisingly' indicates anagramming the letters (a surprising ordering of the letters).
'heroism' is an anagram of 'imehors'.
'tome' going around 'imehors' is 'tomimehorse'.
'pan'+'tomimehorse'='PANTOMIME HORSE'
Can you help me to learn more?
(Other definitions for pantomime horse that I've seen before include "Costume for two performers" , "Christmas show character" , "Christmas double act" .)