Ingenious (11)
There are a few possibilities for this:
resourceful
'ingenious' is the definition.
(I know that ingenious can be written as clever)
This is the entire clue.
(Other definitions for clever that I've seen before include "Quick at learning and understanding" , "Skilful, adroit" , "Mentally quick and resourceful" , "Quick-minded" , "Smart or shrewd" .)
(Other definitions for artful that I've seen before include "showing craft?" , "Crafty like Dicken's Dodger" , "Cunning, wily" , "Crafty or cunning" , "Giving a false appearance of frankness" .)
(Other definitions for subtle that I've seen before include "'Elusive, delicate (6)'" , "Bustle about being delicate" , "Not immediately obvious, understated" , "'Fine, elusive (6)'" , "Delicate - crafty - indirect" .)
'ingenious' is the definition.
(thesaurus)
This is the entire clue.
(Other definitions for resourceful that I've seen before include "Quick-witted" , "Quick to find ways of overcoming difficulties" , "Clever, ingenious" , "Able to find ways of coping with problems" , "ingenuity" .)