Ace artist in clay getting loot (6)
I believe the answer is:
maraud
'loot' is the definition.
(thesaurus)
'ace artist in clay' is the wordplay.
'ace' becomes 'a'.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'in' means one lot of letters goes inside another.
'clay' becomes 'mud' ('mud' can be a synonym of 'clay').
'a'+'ra'='ara'
'ara' put into 'mud' is 'MARAUD'.
'getting' acts as a link.
(Other definitions for maraud that I've seen before include "Harry" , "Raid and plunder" , "Go in search of plunder" , "Go plundering" , "Wander in search of plunder" .)