Foe had run into unprecedented difficulty (7-2)
I believe the answer is:
unheard-of
'into unprecedented difficulty' is the definition.
I can't judge whether this defines the answer.
'foe had run' is the wordplay.
'foe had run' anagrams to 'UNHEARD-OF'.
However, I'm unsure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for unheard-of that I've seen before include "Without precedent" , "Previously unknown" , "Inconceivable" , "Not previously known or done - inaudible?" , "Unknown - novel" .)