Fifteensquared

An IoS towards the harder end of the spectrum, I thought.  There were quite some answers that had to be teased out, including the 4 long anagrams, of which I found 8 down easiest of the lot.  Thank you to Raich.  Definitions are underlined in the clues.  [[The pictures at the bottom, between them, share 2 unidentified links to the puzzle.]]

Across
1 Diplomat with no love for grudging discontent (4)

ENVY : “envoy”(Diplomat) minus(with no) “o”(the letter that looks like zero,love in tennis scores).

Answer: One of the seven deadly sins (see 13 across).

3 Mother’s seen with copper in the German capital (8)

DAMASCUS : [MA's(Mother's) plus(seen with) CU(chemical symbol for the element copper)] contained in(in) DAS(German for the definite article “the”).

Answer: Capital city of Syria.

10 Police left soccer ground missing finish of half – that’s rare (10,5)

COLLECTOR’S PIECE : Anagram of(ground) “Police left soccer ” minus(missing) “f”[the last letter(finish) of "half "].

11 Opt for change, withdrawing fuel investments (9)

PORTFOLIO : Anagram of(change) OPT FOR + reversal of(withdrawing) OIL(fuel).

12 Arrange tennis, say, when pressure’s off (4)

SORT : “sport”(an example of which, say, is “tennis “) minus(when …’s off) “p”(symbol in physics for “pressure“).

13 Ireland look involved in, say, 1A cut (7)

SIRLOIN : [IR(abbrev. for Ireland,the Irish Republic) + LO(look, as in "lo and behold")] contained in(involved in) SIN(an example of which, say, is “envy”, the answer in 1A).

Answer: A prime cut of meat, usually beef.

15 Girl from Venezuela – Inez (6)

ELAINE : Hidden in(from) Venezuela – Inez.

17 Uncertainty after daughter rebuffed official in quarrel (6)

DIFFER : IF(a qualification,uncertainty) placed after(after) D(abbrev. for “daughter “) + reversal of(rebuffed) REF(short for “referee”,the sports official).

Defn. and Answer: As verbs.

19 Ship‘s journey curtailed by specialised military unit (7)

TRIREME : “trip”(a journey) minus its last letter(curtailed) plus(by) REME(abbrev. for the Royal Electrical and Mechanical Engineers, a specialised unit in the British military).

Answer: An ancient Greek or Roman warship with 3 tiers of oars on each side.

20 21, dead – at rest (4)

ABED : ABE(Lincoln, past US president,answer to 21across) + D(abbrev. for “dead“).

21 Wilson once, last of group to live beside National Theatre (9)

PRESIDENT : P(last letter of “group“) + RESIDE(to live) plus(beside) NT(abbrev. for the Royal National Theatre in the UK).

Defn: A reference to Woodrow Wilson, once President of the USA.

24 Players aren’t cross? Right? Wrong! (6,9)

STRING ORCHESTRA : Anagram of(Wrong) AREN’T CROSS? RIGHT.

25 Last to go in at Lord’s or the Spanish high jump, say? That’s hard (8)

ELEVENTH : EL(Spanish for the definite article “the“) + EVENT(an example of which,say, is the high jump) + H(abbrev. for “hard“).

Answer:  At Lord’s Cricket Ground, the last to go in to bat is the eleventh man in a cricket team.

26 Difficult journey coming back in bleaker tundra (4)

TREK : Reversal of(coming back) and hidden in(in) “bleaker tundra“.

Down
1 College in awkward impasse seeking to avoid reality (8)

ESCAPISM : C(abbrev. for “College“) contained in(in) anagram of(awkward) IMPASSE.  Defn:  As a noun.

2 More reprehensible organ has leading trio upset (5)

VILER : “liver”(an internal organ) with(has) reversal of(upset) its first three letters(leading trio).

4 Corona and beer as troubled euro is safeguarded? (7)

AUREOLE : ALE(beer) containing(… is safeguarded) anagram of(troubled) EURO.  And Corona, of course, is a brand of beer -  click here to see some raunchy ads, but only if you want to.

Answer: In astronomy a faintly luminous envelope around a celestial body, its corona.

5 Nice Department seems impartial after reform (5-9)

ALPES-MARITIMES : Anagram of(after reform) SEEMS IMPARTIAL.

Answer: The Department (an administrative division) in France of which the city of Nice is the capital.

6 Risk as King replaces hospital’s official authorisation (9)

CLEARANCE : “chance”( Risk as a verb or noun) with LEAR(the Shakespearean King) replacing(replaces) “h”(abbrev. for hospital).

7 Get rid of storage building (4)

SHED : Double defn.

8 Cliff scene done in new way showing aplomb (4-10)

SELF-CONFIDENCE : Anagram of(in new way) CLIFF SCENE DONE.

9 Hot bread lecturer dropped (6)

STOLEN : “stollen”(a sweet bread, from the German for a wooden post, reflecting its shape) minus(dropped) “l”(abbrev. for “lecturer“).

Defn: Slang for any item that’s been illegally obtained.

14 Financially compensate me after battle with bruiser? (9)

REIMBURSE : Anagram of(after battle) [ME + BRUISER].

16 Abandoned reserve supply in artists’ quarter (4,4)

LEFT BANK : LEFT(deserted,Abandoned) + BANK(a reserve supply set aside).

Answer: The area in Paris besides the Seine where artists and the like congregate.

18 Harmony as painter’s first to praise drink (7)

RAPPORT : RA(a member of the Royal Academy,painter) + initial letter of(first to) “praise” + PORT(fortified alcoholic drink).

19 From that place the National Curriculum initially emerged (6)

THENCE : THE + NC(abbrev. for the National Curriculum in the British education system) + E[initial letter of(initially) "emerged "].

22 Pierce America’s heart when leader’s away (5)

ENTER : “center”[spelling in America of "centre"( heart)] minus(when …’s away) its initial letter(leader).

23 Key feature of supermarket by the sound of it (4)

ISLE : Homophone of(by the sound of it)”aisle”(a feature of supermarkets).

Defn: A small low island or bank, especially in the Caribbean, also spelled as “cay”.

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