Attacker of Satan cunningly framing canvas (9)
I believe the answer is:
assailant
'attacker' is the definition.
(I know that attacker can be written as assailant)
'satan cunningly framing canvas' is the wordplay.
'cunningly' indicates an anagram (a cunning or tricky form of the letters).
'framing' is an insertion indicator (inserted letters are framed by the outside letters).
'canvas' becomes 'sail' (synonyms).
'satan' with letters rearranged gives 'asant'.
'asant' enclosing 'sail' is 'ASSAILANT'.
'of' acts as a link.
(Other definitions for assailant that I've seen before include "who is on the offensive?" , "One attacking another" , "Aggressive sort" , "Who would tear into" , "Attacking person" .)