Across:
   3. Northern town may require housing (3)
   9. Senior academic position, one among amazing top four in 3? (5)
  10. French? I, lad, am mostly Mexican, having tortilla within! (9)
  11. Vein of dense ore hit, naturally returning rich material for illuminating works (10)
  12. Desire to get swilling? Sing about this! (4)
  14. Muddled final steps of treatments, making opposite of blessing (5)
  15. Myth of 18's 14 appeals to this lunatic lured into urban area (9)
  16. Sung unusually, strangely, oddly, with extreme extremes (7)
  18. Chap with a poor 7? No such ends for someone like 13! (7)
  20. Bit of Florida landscape where elder gave out (9)
  22. KKK in Brooklyn County? (5)
  24. Grave place to doctor (4)
  25. Disgrace as land case is lost (10)
  27. He was there when contents of 13's 24 revealed: 9 and a trove of no regular pieces (9)
  28. Where the most vulnerable live, caught in crossfire & turmoil around (5)
  29. Can 6 be reversed? (3)
Down:
   1. Cartoon character, his cat cry awful once Itchy start's out? (8)
   2. He was there when contents of 13's 24 revealed: 9s (their regular pieces) (6)
   3. Backward-looking discipline has principal saying sorry, with previous head replaced by emerging leader (11)
   4. Went back over and over with German 2 (8)
   5. Make plot as one with time to go swinging machetes (6)
   6. Bit of an infestation of genital region? (3)
   7. Cabal is active around Italian capital... an especially famous one in Vatican City (8)
   8. Loudly proclaim a victory, getting back land among the hills (6)
  13. Fail dramatically with bad actor coming between you and one in France who rested in the 8 of the 22 (11)
  17. They may make 5s, optimistically intermingling deer with rams (8)
  18. Expecting to name a new government, Egypt rounds previous leaders up (8)
  19. High emotion in his teary performance (8)
  20. Lure new trainee after first four left (6)
  21. A sweetheart gets caught in recess (6)
  23. Ridiculous denial, but well executed (6)
  26. Energy beam ruined 3 (3)