Ex Post Facto (Solution)

by Derek Kisman; idea by Tom Yue

This looks like a crossword, and it is a crossword, but a very unusual one. There are no numbers, and some mysterious unordered letters next to each clue. And the title, Ex Post Facto, means "after the fact". What's going on?

Well, as it turns out, this crossword was solved once before, in a very linear fashion (each answer written in intersects with the previous answer), and you are being given enough information to retrace the solver's steps. The letters next to each clue are the letters the solver had already entered into the puzzle when he solved that clue.

Of course, your first step has to be reconstructing the final solution. This is easier said than done, since some entries have barely any information. But it's fairly dense for a Fill-In, so going back and forth should enable you to solve all the given clues:

- ORSO                     About
A HAZY                     Blurred
A TRALA                    Carefree song syllables
A NYAN                     Colorful cat
A GAIA                     Earth Goddess
A SRA                      Mexico Mrs.
A ASIA                     Polo venue?
A ARENA                    Venue
E ABATE                    Let up
G GLIBC                    Essential programming package
H PSHA                     "Yeah, right!"
I WIN                      Triumph
L POOL                     Hotel amenity
L LNS                      Math funcs.
L AXL                      Rose of rock
L DAMOSEL                  Young maiden: Archaic
N URN                      Coffee container
N NED                      Reli-diddly-igious guy
O KILO                     Drug unit
P VEEP                     Dick or Joe, recently
R RAS                      ___ al Ghul
R ARAN                     Armored Samus
R SARA                     Gilbert of "Roseanne" and "The Big Bang Theory"
S USSR                     Longtime U.S. foe
S TSA                      They have wands: Abbr.
T TINTYPE                  Old-style photo
U MUGS                     Coffee containers
U SLUE                     Swivel
V VALOR                    Heroism
AA VAYA                    ___ con Dios
AE ENOLA                   Gay bomber?
BR BRAVO                   "Amazing!"
HT ACTH                    Pituitary hormone
KS SKIES                   Hopefully they're blue
LO ALOT                    Oodles
LY LYDIA                   Ancient kingdom in western Anatolia
NO HATON                   Hang one's ___ (trust)
PW SWAP                    Fair trade
AIS AISHA                  Muhammad's favorite wife
ASS ASSESS                 Evaluate
ASS SHERPAS                Hillary's helpers
CEL ONCLE                  Frere de mere ou pere
ENO SEGNO                  Repetition mark, in music
ETT EATIT                  Motherly advice from Weird Al
HMS HELMS                  Steers a ship
IOS STOLI                  Popular vodka, informally
ENOT LEPTON                Neutrino, for one
ABEOT NOTBEATEN            Still in the running
ABGOT GATORBOWL            Annual Florida football game
AOTTY YOTTAMETER           One is 105 million light years
DELRY ELDERLY              Aged
INOST ENTERSINTO           Signs, as an agreement
AEEGLR ALTEREGOS           Kent and Wayne
AELNSV SVENGALI            Fictional hypnotist
CIPRRSY SCRIPTORY          Pertaining to writing
EINORRSSW REWINDCROSSWORD  What to do next!

Note that 18 clues are actually missing. In most cases this doesn't affect the fill, but there are a couple of grid letters you'll need to infer. The final grid is thus:

MUGS##SWAP#ACTH
BRAVO#KILO#SARA
ENTERSINTO#SPAZ
##ONCLE#ELDERLY
#LRG#USSR#ASIA#
#ABATE#HELMS###
STOLI#SEGNO#NED
REWINDCROSSWORD
AXL#TARPS#EATIT
###LYDIA#GLIBC#
#VEEP#PSHA#TEA#
VANPELT#AISHA##
ALOT#YOTTAMETER
YOLO#ORSO#ARENA
ARAN#NYAN##ENDS

Now you can reconstruct the order in which the clues were solved. As it turns out, the missing 18 answers are the ones which were missing exactly one letter when entered into the grid. Here's the full reconstruction:

1  - ORSO
2  S TSA
3  A NYAN
4  NO HATON
5  H PSHA
6  A GAIA
7  G GLIBC
8  L DAMOSEL
9  A ASIA
10 A TRALA
11 R SARA
12 A HAZY
13 HT ACTH
14 ASS ASSESS
15 (P) SPAZ
16 (R) CAPRI
17 DELRY ELDERLY
18 L POOL
19 O KILO
20 I WIN
21 PW SWAP
22 KS SKIES
23 S USSR
24 U SLUE
25 E ABATE
26 T TINTYPE
27 P VEEP
28 V VALOR
29 R ARAN
30 AE ENOLA
31 LO ALOT
32 AA VAYA
33 (O) YOLO
34 ENOT LEPTON
35 LY LYDIA
36 ASS SHERPAS
37 HMS HELMS
38 L LNS
39 ENO SEGNO
40 AEEGLR ALTEREGOS
41 INOST ENTERSINTO
42 N URN
43 U MUGS
44 (B) MBE
45 BR BRAVO
46 (C) ORC
47 CEL ONCLE
48 ABGOT GATORBOWL
49 L AXL
50 A SRA
51 IOS STOLI
52 AELNSV SVENGALI
53 (L) LRG
54 (E) LATEX
55 EINORRSSW REWINDCROSSWORD
56 (A) DAD
57 (R) TARPS
58 CIPRRSY SCRIPTORY
59 (L) VANPELT
60 (Y) LYON
61 AOTTY YOTTAMETER
62 R RAS
63 A ARENA
64 (S) SMA
65 AIS AISHA
66 ABEOT NOTBEATEN
67 N NED
68 (T) DDT
69 ETT EATIT
70 (A) ERICA
71 (T) TEA
72 (E) WAITHERE
73 (D) END/ENDS, a clear ending to the sequence.

The single letters spell PROB CLEARLY STATED. Interesting, but still not an answer. A quick Google should reveal the Dorothea Brande quote:

"A problem clearly stated is a problem half solved."

Aha! You need to half-solve the puzzle!

There are an odd number of letters, so you can't halve them. The only way to half-solve the puzzle is to write in the first 37 words out of 74. This is the final state when you do:

....##SWAP#ACTH
.....#KILO#SARA
.....SIN.O#SPAZ
##...LE#ELDERLY
#...#USSR#ASIA#
#ABATE#HELMS###
....I#.E..O#...
....N..R..S....
...#T..P.#E....
###LYDIA#GLIBC#
#VEEP#PSHA#...#
VANPE..#AI...##
ALOT#..TTA.....
YOLO#ORSO#.....
ARAN#NYAN##....

You can see the final answer symmetrically positioned in the center: INTERPOSE. How appropriate.