This guide is just to help anyone who might be stuck on some achievements for The Silver Case.

Achievements are arranged in order of story progression. Use the side menu to navigate quickly if you're just looking for one. I've grouped all the story achievements together since they don't need any fiddling with. Tried to keep it as spoiler-free as possible.

Achievements that are not story-related are all missable. For Transmitter side, they are in #0 Lunatic, #1 Decoyman, #2 Spectrum, #3 Parade and #5 Lifecut. For Placebo side, Turtle Lover must be done before the turtle is gone (or load up a chapter and grind it out). Play those chapters carefully.

Details
Story-related: 14
Missable: 11
Minimum number of playthroughs: 1
Glitched: 0
Difficulty: 4/10, though if you're looking to get a perfect game, you may have trouble with one or two fussier ones.

Missable achievement locations
#0 lunatic
Avid Reader

#1 decoyman
Follows Orders
It must be important...
All Green

#2 spectrum
Your score is in your heart
My other job is property manager

#3 parade
Investigate Orderly

#5 lifecut
Dancer in the Dark

#25 whiteout
A 25th Ward?

Placebo cases
Turtle Lover

Living in the Past can be obtained in any chapter.

Lunatic
Survived the Lunatic case.
Complete Lunatic.

Met Kamui
Survived the Decoyman case.
Complete Decoyman.

Many Shades
Survived the spectrum case.
Complete Spectrum.

Grand Marshal
Survived the Parade case.
Complete Parade.

Behind the Net
Survived the Kamuidrome case.
Complete Kamuidrome.

A New Birth?
Survived the Lifecut case.
Complete Lifecut.

Resolution?
Completed the danwa case.
Complete danwa. You must finish the other investigations before danwa becomes available (it is marked with a case !).

White out prologue
Survived the White out prologue case.
Complete whiteout. This is the final case in the transmitter arc (left arrow) for now. You must finish both Transmitter and Placebo arcs (up to danwa and Yami respectively) to access #25 whiteout.

Dream
Completed the YUME investigation.
Complete Yume. From the case selection screen, click the right arrow for report*1. You must complete #1 Decoyman.

Flower
Completed the HANA investigation.
Complete Hana. From the case selection screen, click the right arrow for report*2.You must complete #2 Spectrum.

Moon
Completed the TSUKI investigation.
Complete Tsuki. From the case selection screen, click the right arrow for report*3. You must complete #3 Parade.

Love
Completed the AI investigation.
Complete Ai. From the case selection screen, click the right arrow for report*4. You must complete #4 Kamuidrome.

Light
Completed the HIKARI investigation.
Complete Hikari. From the case selection screen, click the right arrow for report*5. You must complete #5 Lifecut.

Darkness
Completed the YAMI investigation.
From the case selection screen, click the right arrow for report*6. You must complete #5 Lifecut and the danwa case. (Thanks to flashmoZZg for pointing the requirements out!)

Avid Reader*
Collected all Comic Beams.
In #0: Lunatic. There are two comic beams in Cauliflower. One is at 1F. While facing the elevator to 2F, do a 180 degree turn and look down. The magazine is there. The second one is at the roof. Turn left and walk until you notice a ladder. Look down. The magazine is on the floor.

Follows Orders*
Completed the Forest exactly as ordered.
In #1: decoyman. Follow the green arrows on your minimap all the way until the forest scene ends. Don't diverge and you'll be fine.

It must be important...*
Let a phone ring for a long time.
In #1: decoyman. When you're in your apartment for the first time after the cinematics, after checking the computer and the TV, the phone will ring. Don't answer right away; let it ring! I let it ring about 20-30 times before picking it up just in case.

All Green
Completed HIT & BLOW in 5 or fewer attempts.
The puzzle you must complete within 5 tries is the first puzzle you encounter in Babylon, in #1: decoyman. The number is apparently randomized, and using the magnifying glass to solve it doesn't work. I'm also unsure if you must reload after failing for the achievement to pop, or if you can keep exiting and trying again.

Here's a solution contributed by ＡＮＩＭＥ　ＰＲＯ & updated by Drax:

引用自 ＡＮＩＭＥ　ＰＲＯ ：

For the hit & blow puzzle, there's a solver that can be found here[under-dev.appspot.com] (thanks for the updated link, Drax!). Extract from zip. Enter 0123 as the first try in-game, and then type "X(space)Y" where X is the number of greens (hits) and Y is the number of reds (blows), into your program and hit enter. You should have your answer in 4 to 5 tries.

I've tested and gotten the achievement this way. Every time the solver generates an answer, key it in and repeat the number of greens and reds. If the program doesn't generate the final answer ("It's xxxx!") in 5 tries, close it, reload your save in-game and reload the program, put 0123 as the first try again, and repeat the process.

Reference for those of you who missed the puzzle:

Your score is in your heart.*
Correctly answered all trivia questions.
As it states: correctly answer all 100 questions Morikawa throws at you in #2: spectrum. Damnit.

I noted the letters down wrongly for some questions, so I'm just going to put the right answers to all the questions here without the letters:

1. Mizoguchi
   
2. Wumpa fruit
   
3. Batman
   
4. Entruscan Shrew
   
5. 1995
   
6. Tsugaru Strait
   
7. Okinawa
   
8. Dr. Pepper
   
9. J. Fox
   
10. Atari
    
11. Hiruma
    
12. Satoru Nakajima
    
13. Strawweight
    
14. Truffles
    
15. Atlanta, USA
    
16. 4
    
17. Momotaro
    
18. The thing called love
    
19. Mr. Watson, come here
    
20. Noodles
    
21. 301
    
22. Ichiro Suzuki
    
23. 2 (judo)
    
24. 1996 (Playstation)
    
25. Akebono
    
26. Upper Egypt
    
27. Amaterasu
    
28. Truman
    
29. 1968
    
30. Executive
    
31. Accidental death
    
32. Croatia
    
33. Princess Mononoke
    
34. Green tea
    
35. A fistful of dollars
    
36. Chemical reaction
    
37. Diet
    
38. Blue whale
    
39. ARPANET
    
40. Olympus Mons
    
41. None
    
42. Bogey
    
43. Tatsumi Fujinami
    
44. Stewed fish and other ingredients
    
45. Giant Steps
    
46. Replicant
    
47. Yamato
    
48. Tetris
    
49. Opal
    
50. Lee Jun-Fan
    
51. Revenge
    
52. Superintendant
    
53. Red
    
54. Hubble
    
55. Trumpet
    
56. Einstein
    
57. France
    
58. Netherlands
    
59. Merci
    
60. PKO
    
61. Alcohol
    
62. Super Smash Bros
    
63. Ryoma Sakamoto
    
64. 13 years old
    
65. 52 (deck of cards)
    
66. James Cameron
    
67. Elvis Presley
    
68. Sahara
    
69. 200m
    
70. Tetsugoro Kusabi
    
71. 5th floor
    
72. Flush
    
73. Washington, D.C.
    
74. Ladies Love
    
75. Baccarat
    
76. Redwood
    
77. Germany
    
78. A rabbit
    
79. United Kingdom
    
80. Sumio
    
81. Heart attack
    
82. Playstation
    
83. K2
    
84. Skinner
    
85. Klondike
    
86. Nago
    
87. Mozart
    
88. Neil Armstrong
    
89. France
    
90. Eric Cantona
    
91. A sticker stuck behind his keyhole
    
92. The One
    
93. Blue whale
    
94. Phonograph
    
95. Shirano River
    
96. John McClane
    
97. Ferrari
    
98. Gold
    
99. ABBA
    
100. Odin

My other job is property manager.*
Explored the entirety of the Typhoon apartment complex.
In #02: Spectrum. This is best done during the 3rd visit to Typhoon when you're asked to question everyone. I cleared the first 4 floors on the first visit, though, and still got the achievement later on. You need to interact with all the rooms and the extra triangle points to get the achievement.

While facing the staircase on every level:
Typhoon 1F: room 101 on left. Clear triangle past 101 too.
Typhoon 2F: room 201 on left. Clear the triangle past 201 too. Room 202, 203 on right.
Typhoon 3F: room 301 on left. Clear triangle past 301 too. Room 302, 303 on right.
Typhoon 4F: room 401 on left. Clear triangle past 401 too. Room 402, 403 on right.
Typhoon 5F: one triangle point on the left. Room 502 on right.

As part of the story, you'll explore the parking lot and other areas, which will count towards the achievement.

You should get the achievement by the time you finish the questioning.

Investigate Orderly
Read the Mikumo village documents in order.
This one is tricky to get. Be sure you don't miss it. At the end of #3 parade, you will be in Warehouse 24. After getting into the room with rows and rows of file cabinets, you will have to read some documents.

It's fine if you miss the order the first round. After you read all the documents, regardless of order, a secret wall will unlock, revealing a final document. Before you read it, go back to the door that you came from and face the cabinets again (like when you first entered the room).

You have to read the documents again, but in order this time. There are two aisles, each with two contact points (skipping the hidden wall).

Right aisle
First contact point: #4 (left), #1 (right)
Second contact point: #6 (left), #2 (right)

Left aisle
First contact point: #7 (left), #3 (right)
Second contact point: #8 (left), #5 (right)

Facing the wall with the door behind you (always face the wall when you go back to the door):

Right > First point > Right (#1)
Straight > Second Point > Right (#2)
Back to door > Left > First Point > Right (#3)
Back to door > Right > First Point > Left (#4)
Back to door > Left > Second Point > Right (#5)
Back to door > Right > Second Point > Left (#6)
Back to door > Left > First Point > Left (#7)
Straight > Second Point > Left (#8)
Last hidden door on left aisle: #9

Dancer in the Dark
Collected both volumes of Kurayami Dance.
In #5 Lifecut. There are two volumes.

The first is at the Kinjo Building, 4F, in front of the Flower Sun & Bar. Look down.
The second is in the Shelter Plaza when you first enter, left side of the fountain. Look down.

Living in the Past
This one is simple. At the main menu, go to settings, then remaster settings. Switch everything back to Original. Then load up a chapter and play it through till the end. For those of you who haven't done danwa, you can get both Resolution? and this achievement in one playthrough of that chapter. It's one of the shorter ones, and you can get a drink while the credits roll.

Turtle Lover
Talked to Red 50 times.
Load any Placebo chapter and keep interacting with the turtle Red until the achievement pops. As the description says, you have to interact with it 50 times. You can do it consecutively. I got it on #2 HANA, since later on the turtle isn't there anymore.

A 25th Ward?
Learned about the attempt to build a 25th ward.
In #25 Whiteout. When you finally gain control, you'll be in a room full of couches. Look around until you find a poster lying on a green couch and interact with it. The achievement will pop once you view the poster.

Thanks for reading! Do let me know if there are any mistakes, or if you have tips to offer - even if it's just sugggestions on how to organise info. It's my first time writing up a guide.

I wrote this based on what I've done in-game that worked, so if there are alternative methods or problems, I welcome the input and feedback.

Hope this at least makes someone's life better out there. ^u^