No 12693, Thursday 01 Aug 2019, Hypatia

Solved while at Zion National Park, Utah

ACROSS
1   Blinking light's best, when dancing around room oddly (6) STROBE {ST{RoOm}BE*}
4   In good condition, wish for loads of money? (6) WEALTH {-h+w)WEALTH (Addendum - (-h+w)WEALTH - See comments)
9   At entrance of Zoo, several gave a little monkey nuts (4) ZANY {Zoo}{mANY}
10 According to Spooner, additionally, the chamber had a block  (3,3,4) HIT THE WALL (with the hall to hit the wall)
11 Fight with knight at North American capital (6) VIENNA {VIE}{N}{NA}
12 Once again, request to feature Chennai's first chronicler (8) RECORDER {RE{Ch...i}ORDER}
13 Gutless Rakshasa sacrificed until Brahma created miniature (9) THUMBNAIL {UNTIL+BraHMA}*
15 Abandon daughter, serving time in pound (4) QUID {QUIt}{D}
16 Fail to expel student in panic (4) FUNK FlUNK
17 Chew algae with old rum for piles (1,4,4) A GOOD DEAL {ALGAE}* over {O}{ODD}
21 MP, for one is a jerk, involved in horseplay? (8) POLITICO {POL{1}{TIC}O}
22 Defer to the woman, not only admire (6) SHELVE {SHE}{LoVE}
24 Major transformation has each angel's crowdsourcing (1,3,6) A SEA CHANGE [T]
25 Couple kiss and hug outside but curse (4) JINX {JoIN}{X}
26 Being different, I typically hid (6) ENTITY [T]
27 Alas, broke-up and left separately, struggling to express once more (6) RETYPE sEPaRaTElY*

DOWN
1   Submissive, like an East European? (7) SLAVISH [DD]
2   Perhaps Satyajit's working material (5) RAYON {RAY}{ON}
3   Mind embracing a hot country (7) BAHRAIN {B{A}{H}RAIN}
5   As moral principles these possibly chastise (6) ETHICS CHasTISE* [CA] &lit
6   Maybe, Marsh owl (3,6) LOW GROUND {OWL}* [RA]
7   Old weapon keeping pack of animals outside a pound (7) HALBERD {H{A}{LB}ERD}

8   P Base? (8-5) STARTING-POINT Definition by example
14 Beggar isn't able to follow, mind addled with drug (9) MENDICANT {CAN'T} after {M{E}NDI*}
16 An indication of interest in a stock index, say (7) FOOTSIE [DD]
18. Indecent alumnus is recognized on the telephone (7) OBSCENE {OB}{SCENE}(~seen)
19 Move forward supply (7) ADVANCE [DD]
20 Clothing in which a soldier keeps ahead? (3,3) TIN HAT [CD?]
23 Starting to explore new joints, obviously you have fun (5) ENJOY Acrostic

Reference List
Wish = W, Loads = H, Knight = N, Daughter = D, Student = L, Old = O, Rum = ODD, Only = O, Kiss = X, Hug = O, Hot = H, Pound = LB, Drug = E, Alumnus = OB(Old Boy)

GRID