God is central to bloodiness (4)
I believe the answer is:
odin
'god' is the definition.
(Norse god)
'central to bloodiness' is the wordplay.
'central to' says the answer is hidden in the clue.
'ODIN' is hidden within 'bloodiness'.
'is' acts as a link.
(Other definitions for odin that I've seen before include "Legendary ruler" , "Legendary Scandinavian" , "Supreme god of Scandanavian myth" , "God - I nod (anag)" , "divine figure" .)