PHSSTHPOK kicks off the week…
A fun puzzle with some lovely surfaces. A good Monday starter.
Thanks PHSSTHPOK!

ACROSS
7. Evil foundation (4)
BASE
8. Content of Vincent’s journal is sensational (10)
INCENDIARY
[v]INCEN[t] (content of) + DIARY (journal)
10. Fur and hollow incisors define mammals (6)
COATIS
COAT (fur) and I[ncisor]S (hollow)
11. Fool swallows French article about how one speaks (8)
IDIOLECT
IDIOT (fool) swallows (LE (French article) + C (about))
12. Steep articulated fence causes uproar (8)
BROUHAHA
“brew” = BROU (steep, “articulated”) + HAHA (fence)
13. Blackmail former wife — a civil wrong (6)
EXTORT
EX (former wife) + TORT (a civil wrong)
15. Alien system, short of success, runs a caliphate atrociously (5,8)
ALPHA CENTAURI
(RUN[s] (short of S (success)) A CALIPHATE)* (*atrociously)
18. Fix gold buttons opening coat (6)
BEDAUB
BED (fix) + AU (gold) + B[uttons] (opening)
20. Bond transfer connected with pound (8)
HANDCUFF
HAND (transfer) connected with CUFF (pound)
22. Defence lawyers forbid intervention by heads of International Court (8)
BARBICAN
(BAR (lawyers) + BAN (forbid)) intervention by (I[nternational] C[ourt] (heads of))
24. One flees corrupt regime? (6)
EMIGRE
25. Insect I preserve in liquid (10)
ANTIFREEZE
ANT (insect) + I + FREEZE (preserve)
26. Smell butt in front (4)
NOSE
DOWN
1. Product of cloud computing not yet available? (10)
VAPOURWARE
Cryptic definition (or possibly a double (cryptic) definition)
2. Police pressure to interrogate source of power (4,4)
HEAT PUMP
HEAT (police pressure) + PUMP (to interrogate)
3. Pollution in Massachusetts after motorway is contaminated with arsenic (6)
MIASMA
(MA (Massachusetts) after MI (motorway)) is contaminated with AS (arsenic)
4. Furious after drug displacing sodium broke (8)
INDIGENT
INDIGNANT (furious, after E (drug) replacing NA (sodium))
5. Savage noises start fading away like Deep Purple? (6)
VIOLET
VIOLE[n]T (savage, N[oises] (start) fading away)
6. Lizard caught gigantic bird (4)
CROC
C (caught) + ROC (gigantic bird)
9. Environmental catastrophe when chemical agent disintegrates (7,6)
CLIMATE CHANGE
(CHEMICAL AGENT)* (*disintegrates)
14. Destroying of terrains such as the Amazon (10)
RAINFOREST
(OF TERRAINS)* (*destroying)
16. Tuna processed in Barcelona but not Norway (8)
ALBACORE
(BARCELO[n]A (not N (Norway)))* (*processed)
17. Oils joints after removing cover (8)
UNCTIONS
[j]UNCTIONS (joints, after removing cover)
19. While away long boring enquiry interviewing talking heads (6)
ALBEIT
A[way] L[ong] B[oring] E[nquiry] I[nterviewing] T[alking] (heads)
21. Did badger get left out as required? (6)
NEEDED
NEED[l]ED (did badger, L (left) out)
23. Old lady drawn without head (4)
AUNT
[g]AUNT (drawn, without head)
I’ve been doing cryptic crosswords for almost exactly a year to the day, and this is the first time that I’ve not only completed the grid but also got all of the parsings without help. Small victories!
I read NOSE as a triple definition: Smell, butt in, front. Thanks for the blog.
Congrats Heather@1.
My faves today: BROUHAHA, VAPOURWARE and the CLIMATE CHANGE-RAINFOREST couple.
Agree with Cineraria@2 on NOSE.
Thanks Phssthpok and Teacow.
Loved this, especially 1d VAPOURWARE (Duke Nukem Forever); 11a IDIOLECT(first heard in A Very Peculiar Practice [1986–8]);
and 19d ALBEIT, an acrostic, with a ‘Divide & Conquer’ at each end. Cineraria@2 has got 26a on the NOSE.
Heather @1 – congratulations! Many more to come we hope. And this was not right at the easy end either.
Well done Heather
I found this site a great help on my cryptic journey
Thanks to everyone for the encouragement!
Feels like a long time since I saw a Phssthpok puzzle – this was great. Many fine words and excellent constructions, too many to pick a favorite. I had a minor quibble about 12a since I had the belief that a ha-ha was a sunken feature i.e. a trench rather than a fence. But not a big issue. Thank you to both.
12ac: ODE 2010 p 789 and Chambers 2016 p 688 both define ha-ha as a ditch containing a fence, but Collins 2023 p 881 gives “a wall or other boundary that is set in a ditch so as not to interrupt the landscape”. In such cases, it seems reasonable to allow a setter to use either meaning.