This Guide will focus on how to get all achievements the easiest and fastest way. Please feel free to ask questions in the comments if you have any questions

THERE IS ONLY 1 MISSABLE ACHIEVEMENT IN THE GAME SO MAKE SURE TO LOOK DOWN AT THE ACHIEVEMENT "BLACK ON BLONDE" UNDER THE MISC SECTION

These Achievements will get unlocked as you progress through the story so don't put to much thought into them.
Caesar The Thief
Defeat Caesar in Mandrione.


Magda The Possessed
Exorcise Magda in Appia Street.


Matthew The Gangster
Infiltrate the Titus Twister and defeat Matthew The Gangster.


Enoch Varg The Devil's Son
Exorcise Enoch Varg at the Outer Circle.


Mother Superior
Defeat the Mother Superior in St. Terentius Convent.


Master!
Defeat Ray's Master on Mount Vesuvius.


Head Guard Furius
Defeat Furius inside the Coliseum.


Exorcists Showdown
Defeat the Cardinal in the Vatican Gardens.


Laurentius IV
Defeat Larry and his machine in the Throne Room.


The Gates of Hell
Defeat Lilith and prevent the Gates of Hell from opening.

These achievements are random achievements that require you to do a specific task to unlock them

black on blonde
Misbehave
When you first rescue magda your house keeper/the blonde girl in the house (second boss). you have to type sleep on her 3 times. YOU CANNOT GET THIS ACHIEVEMENT AFTER YOU'VE GOTTEN PAST IT. so make sure to do it after you've finished the mission.

If you by mistake don't get it will you have to delete your save and start over. It's fairly easy to do so fortunately. Go to C:\Users\user\AppData\Local\Textorcist and copy the folder "Textorcist" to a safe spot like your desktop and then delete the folder. Now you just have to open the game and beat the first two bosses. After you've defeated magda go over to her and type sleep three times like explained above.

Brute Force
Fail 3 attempts to solve the Keygen riddle
When in the sewers/dungeon before the boss "The Exorcist Showdown". After you get to "Matthew the gangsters" room guess the code wrong three times to unlock this achievement

You can’t always take a shower
Examine the bidet in Ray’s apartment
Go next to it and press use as it shows

These are challenging achievements that essentially requires you not to take damage as much as possible or entirely

Safe and Sound
Win a fight without losing a single heart.


Unscathed
Win a fight without losing your book.


Perfect Phrase
Type a whole phrase without mistakes.


Perfect Exorcism
Type a whole exorcism without mistakes.


I were able to complete all of these on the "Magda The Possessed" boss after several attempts. It isn't easy but it's the easiest boss to get these on in my opinion. The max combo you can get is 166 though so you won't get all combo achievements with this boss.

You increase your current combo as you continue to write words without pressing a wrong key.
These are all the achievements for combos
Clerical
Score a 30 letters combo.


Blessed
Score a 70 letters combo.


Angelical
Score a 120 letters combo.


Santo
Score a 180 letters combo.


Santissimo
Score a 250 letters combo.


The best boss I found the easiestto get the 250 combo on was the fourth boss "Enoch Varg The Devil's Son". The first 4 stages has relatively easy patterns and then you just have to write the first 4 words of the fifth stage and you'll get a combo of 250.

So the new update was released here the 1st august 2019 with the inclusion of trinkets and hardcore bosses. I'll add the update at the end of this section but the core of it is that you now have to beat every boss 3 times to get all the trinkets from that specific boss. It's a huge pain in the butt to do and I can't see why anyone would do it unless they had a friend to split up the work with.

New Achievements
You have to get all 30 of the new trinkets. You have to beat each boss 3 times but read below for further info on how it all works. the last achievements is beating all the bosses on hardcore mode and then you'll have gotten all of the remaining achievements.

SPOILERS
BOSS RUSH:
After finishing the game, players will unlock the Boss Rush mode by continuing the game.
This game mode can be accessed from the title screen and features all bosses in a row inside a new arena, with its own leaderboard and Trinkets enabled.

TRINKETS:
There are 30 (+1) Trinkets to be earned in the Story Mode.
Every Trinket can grant a bonus and lower the player’s score or can grant a malus and raise the player’s score. To get a Trinket, the player must defeat bosses and every boss can drop three Trinkets. Tier 1 Trinkets are dropped just by beating a boss, tier 2 Trinkets are dropped if the player beat a boss without losing hearts and tier 3 Trinkets are dropped if the player beats a Boss without any typing errors. Players start with 0 slots and by simply progressing with the story they will gain slots up to a maximum of 5. Trinkets can be equipped at the wardrobe in the hub. While equipping those, some simple rules are applied: players cannot equip as many Bonus Trinkets so the Score percentage is equal or less than 0%. Only one Action Trinket can be equipped at a time (Action Trinkets are activated by pressing SPACE), and the Monocle is the only Trinket used to access Hardcore Boss Fights and it's the only Trinket that must be equipped alone.

THE MONOCLE AND HARDCORE BOSS FIGHTS:
After finishing the game, players will get the Monocle (31st Trinket) by continuing the game after watching the cutscene. This particular Trinket comes with a stone to be found in the hub. By equipping this special Trinket, players will be granted access to the Hardcore Boss Fights accessible from the world map. Hardcore Bosses are the same story bosses, but they behave as follows: all moves are shuffled, the bosses attack relentlessly without down-times, spells are shuffled, players have only one life. After beating a Hardcore Boss, the stone in the hub will gain a new piece until completion. With the Monocle equipped, the player’s score is highly raised and goes in the same leaderboards as the story mode.

Note: The beta branch version has all the trinkets already unlocked and you can fight all the bosses right from the start. The leaderboards are only in test mode and the score will not be visible in the regular version