King of the gods is back in Egypt (4)
I believe the answer is:
suez
'in egypt' is the definition.
(I know that Suez is part of Egypt)
'king of the gods is back' is the wordplay.
'king of the gods' becomes 'zeus' (I've seen this before).
'is back' is a reversal indicator.
'zeus' reversed gives 'SUEZ'.
(Other definitions for suez that I've seen before include "Port of NE Egypt" , "A Passage to India" , "Nineteen fifty six crisis" , "Isthmus connecting Egypt to Sinai" , "Canal linking Red Sea to Mediterranean" .)