Hooded killer, man on horse, artist depicts (4,5)
I believe the answer is:
king cobra
'hooded killer' is the definition.
(I've seen this before)
'man on horse artist depicts' is the wordplay.
'man' becomes 'k' (abbreviation for king, a chess man).
'on' means one lot of letters go next to another.
'horse' becomes 'cob' (type of horse).
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'depicts' becomes 'ing' (I can't explain this - if you can you should believe this answer much more).
'cob'+'ra'='cobra'
'cobra' after 'ing' is 'ingcobra'.
'k'+'ingcobra'='KING COBRA'
Can you help me to learn more?
(Other definitions for king cobra that I've seen before include "Venomous type" , "hooded killer" , "Hooded giant" , "Large Asiatic snake" , "venomous customer" .)