First I want to sorry for my english, I didn't learn it at school or college, so I can do many mistakes :)
I just hope my english will be understandable.



Most achievements in the game (14/15) are missable.

There are 2 mutually exclusive achievements: "Glass Ceiling" and "Speedhunter".

You can backup your savefile before going to airship, complete "Speedhunter", then restore savefile and grind "Glass Ceiling" and "Card Collector" achievements.

• To open folder with savefile press [Win]+[R] ("Win" key is between left [Ctrl] and [Alt]), and copypaste this text into "Run" dialog:
  
  %USERPROFILE%\AppData\LocalLow\Kyy Games\Trulon
  and press [Enter].

There is only 1 unmissable storyline achievement.

Game Over
Complete the game.


Self-explaining achievement :)

Missable achievements can be completed at any time (but better to do it before point of no return).

Poker Face
Win a battle using only Wildcards.


The easiest way to do it is a small monsters pack (1-2 monsters) before the first visit to Gaudris Castle (for example, your very first enemy in the Haleberry Woods).

Take only the "Protective stance" card.



In combat use only "Wildcards" - 2nd card from the right edge of the screen.



Unscathed
Win a battle without taking any damage.


Be Quick or Be Dead
Defeat all the enemies in a single round.


I did it before my first visit to Gaudris Castle. But it shouldn't be a problem to do it later.

After completing Wayfarer's Holt you should have 2 characters with level 5 or 6. Take only the "Hail of Bolts" card for Gladia and only the "Battering Force" card (reward from side quest in the Wayfarer's Holt) for Ferra, then walk around Meadow Hills to get a "random encounter" event (monsters in those encounters are very weak).



Dirty Tricks
Use Below the Belt on a stunned opponent.


Stun any enemy (use "Stun grenade" or "Soothing wave" card), then use the "Below the Belt" card on a stunned enemy.



Dish Best Served Cold
Finish a battle with Retribution.


Kill last enemy with counterattack by "Retribution" card.

Solution:

• Equip Roth with "Haste", any taunting card ("Shadow Dance" or "Taunt") and "Retribution".
  
  
  
  
• Enter any battle.
  
• Kill all enemies except one.
  
• Lower HP of last enemy to minimal.
  
• Use on Roth "Haste", then taunting card and "Retribution".

Overpowered
Deal over 2000 damage with one attack.


Preparations:

• Upgrade your team to level 20+
  
• (optional) Upgrade Gladia to level 30.
  
• Equipment:
  
  • Gladia:
    
    • Supreme Aggressor (Attack +25)
      
    • Advanced Aggressor (Attack +15)
      
    • Detonating Bolts (Assault Tactics deal double damage)
      
      
      
      
• Cards:
  
  • Gladia:
    
    • Below the Belt
      
    • Furious Missile II (x2) or Furious Missile II + Furious Missile
      
    • Haste (x2)
      
      
      
      
  • Ferra:
    
    • Blast of Frailty
      
    • Invigoration
      
    • Haste
      
      
      
      
  • Valencia:
    
    • Soothing wave
      
      
      
      
  • Roth:
    
    • any character exclusive card
      
      
      
      

Combat:

• Roth:
  
  • use any card.
    
• Valencia:
  
  • use Soothing wave.
    
• Ferra:
  
  • use Haste,
    
  • use Invigoration on Gladia,
    
  • use Blast of Frailty.
    
• Gladia
  
  • use Haste,
    
  • use Furious Missile II,
    
  • use Haste,
    
  • use Furious Missile II,
    
  • use Below the Belt on stunned enemy.
    
    
    

Other missable achievements in order of acquiring during the game progress.

Apt Pupil
Listen to all the advice from Marcus.


At the very beginning of the game after training battle talk to Marcus (multiple times) until you get the achievement.



Family Ties
Visit Dad before leaving to Maelon.


After your first visit to Gaudris Castle go to Home (instead of going to Maelon through Borderlands) and talk to Dad.

It Belongs to a Museum!
Collect all the hidden treasures.


See the "Hidden treasures" section below.

Death of a Salesman
Complete the A Job to Kill for quest.


In the center of the Maelon sity near Wiggs (storyline quest NPC) take the key from a bench.



Then go to the house in the western part of the city. Inside the house read the book on the table in the back room. It will start side quest "A Job to Kill For". Complete this quest and you will get the achievement.

Hunter X Hunter
Slay the Hunter in the Dark.


In the Maelon sity near entrance to the Upper town talk to Maelonian soldier. It will start side quest "A Hunter in the Dark".



Complete this quest and you will get the achievement.

Card Collector
Collect all the tactics from random battles.


Farm all available cards from random encounters.

When i got this achievement i has 38 unique cards - 17 common and 21 character exclusive.

• You will get this achievement while doing Glass Ceiling.

Glass Ceiling
Hit the level cap with a character.


Achieve level 30 with Gladia. Requires plenty of grind. The best place to do it is the first map when you return there from the Maelon.

• Incompatible with the Speedhunter achievement!

Speedhunter
Complete the game in less than 5 hours.


The game isn't so long. It can be completed in 4.5 - 5 hours without crazy rush :) If you will not stuck somewhere.

Ignoring side quests in Maelon city can save around 20-30 minutes.

• Incompatible with the Glass Ceiling achievement!

There are 5 hidden chests on the map related to the "It Belongs to a Museum!" achievement:

• 1st Map: in the Meadow Hills talk to Villager near Mayor. She will ask you for food. Go to the area entrance and take one turnip from the field. Give turnip to Villager and she will reward you with a map.
  
  
  
  1st Chest: to the west of the Meadow Hills.
  
  
  
  
• 2nd map: at your first visit to the Gaudris Castle go to the first room to the left of the entrance and talk to Adventurer there.
  
  
  
  2nd chest: to the east of the Haleberry Woods.
  
  
  
  
• 3rd map: in the Shindusk town after you stole a crate from the warehouse (for the storyline quest "Investigate in Maelon") go to the south of the area and talk to Debtor 2-3 times.
  
  
  
  3rd chest: to the west of the Shindusk.
  
  
  
  
• 4th map: in the Maelon city talk to Merris at the area entrance.
  
  
  
  4th chest: to the south-west of the Maelon city.
  
  
  
  
• 5th map: in the western part of the Maelon city talk to Debtor in red scarf on one of the platforms between the stairs.
  
  
  
  5th chest: to the south of the Shindusk / to the west of Maelon city.