Artist is chasing harmony, the strange creature (7)
I believe the answer is:
chimera
'the strange creature' is the definition.
'chimera' can be an answer for 'creature' (I have seen 'fabulous creature' mean 'chimera' so perhaps 'creature' could also mean 'chimera'). I'm not sure about the 'the strange' bit.
'artist is chasing harmony' is the wordplay.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'is chasing' means one lot of letters go next to another.
'harmony' becomes 'chime' (I am not sure about this - if you are sure you should believe this answer much more).
'ra' after 'chime' is 'CHIMERA'.
Can you help me to learn more?
(Other definitions for chimera that I've seen before include "Illusion" , "Wild notion" , "fabulous beast" , "Race him (anag.)" , "fantasy" .)