Across:
   1. 5 was half 23 and half 4 (8)
   5. Oddly dashing, lost spiritual leader (6)
  10. Flowing goddess, strangely hard pop figure for 21 (9)
  11. Reform hunter, lost temporal leader (5)
  12. Some plumbing primarily dealing with deluges (6)
  13. Make vital error going back not complete and not absolute (8)
  15. She pulls the threads with major tension on ocean (10)
  16. Legless creatures behead six-legged creatures (4)
  19. Our duty is to provide a form of dialogue for Pakistan (4)
  21. 11 built rajah a wall (10)
  24. Quiet pained expression of finding foxes' outside lairs (8)
  25. 5 suddenly stopped taking drug (6)
  27. Young Italy was essentially 5 (5)
  28. Sung about Royal sixes not being passed (9)
  29. 5's nation embraced her finally (6)
  30. Union party of 5 and 11 (8)
Down:
   1. Capital (dough) Siam arranged (9)
   2. Naked phony little crown without head in capital  (7)
   3. One at cape lost head with lack of chaos (8)
   4. As outwardly holy as a sadhu may be (4)
   6. Turn in history book at Christmas perhaps (6)
   7. Health food is about a bunch of flowers (7)
   8. Accustom East to be bearing terrible ruin (5)
   9. Alan who was across the US dollar? (9)
  14. Evil brat's fake meal (9)
  17. Bishops' domains embrace return of good devil: without one they won't allow 18 (9)
  18. Evil gran out wrecking work of 15 (8)
  20. Medico possessed and lost to the drink (7)
  22. Lie about Zion being rebuilt and put on a pedestal (7)
  23. Medico with hair for coat (6)
  24. Questionable greeting for Eastern dish (5)
  26. Group riot madly (4)