English writer into action took on mystery (8)
I believe the answer is:
deepened
'took on mystery' is the definition.
The definition and answer can be both related to change as well as being past participle verbs.
Maybe there's an association between them I don't understand?
'english writer into action' is the wordplay.
'english' becomes 'E' (abbreviation).
'writer' becomes 'pen' (something which writes).
'into' is an insertion indicator.
'action' becomes 'deed' (deed is a kind of action).
'e'+'pen'='epen'
'epen' inserted inside 'deed' is 'DEEPENED'.
Can you help me to learn more?
(Other definitions for deepened that I've seen before include "Made more intense" , "Became more profound" , "Made more profound" .)