Simple pointers for 100% completion. Mostly spoiler-free.
 
 

Story Related

 
All of these should pop up at key points during a first run. The points being;
 
 
The World: (Day 1) as you arrive at the island,
 
Wheel of Fortune (!): (Day 4) after you escape from the maze,
 
Death (!): (Day 4) as you sail towards the ship on the horizon,
 
The Lovers (!): (Day 4) after you dig your way into the earth.
 
 
(!) Note that these three are only available if you do not find a firearm or choose not to use it if found.
 
 
 

Optional

These ones require extra effort on your part and can be missed during a first run.
 
 
The Sun (Prologue to Endgame)
 
 

 
You are offered an equipable lantern at various points throughout your days.
 
Do not pick them up at all till the end of your adventure.
 
 
Strength (Prologue)
 
 

 
There lies a trapdoor to the cellar in the ground level of the lighthouse. Check it out.
 
 
The Tower (Prologue to Day 4)
 
 

 
There is a record player at the top of the lighthouse that you can interact with.
 
Turn it on everytime you get the chance.
 
 
The Star (Day 1)
 
 

 
Your suitcase lies to your left as you start your first day on the pier. Leave it there.
 
Mind though – not carrying it to your abode locks you out of one of the possible endings (Judgement), as well as another achievement (Justice).
 
 
The Emperor (Days 1 to 4)
 
 

 
You find / wake up to patches of dirt in your abode’s floor every single day.
 
Grab the broom from the kitchen and clean them up.
 
 
The Hierophant (Day 1)
 
 

 
There is a cross hung above the bedroom door of your abode. Do not leave home without it.
 
 
The Chariot (Days 2 and 3)
 
 

 
You are hunted by an entity in two different sequences. Do not get caught.
 
 
Temperance (Day 3)
 
 

 
You need to search through the mounds to find the lighthouse key.
 
There are ten mounds around the island. Dig them all.
 
 
The Hermit (Day 3)
 
 

 
You are hunted by the entity. Do not run for the toolshed. Opt for the outhouse instead.
 
 
The Magician (Days 1 to 4)
 
 

 
There is a locked chest at the corner of your bedroom. You need four coins to unlock it.
 
Better slot them in one by one, as you find them.
 
 

 

 

 
Day 1 – Grab your briefcase from the pier and put it on the table.
 
Day 2 – Check around the boat lying on the beach.
 
 

 

 

 
Day 3 – Dig the mound behind the lighthouse.
 
Day 4 – Search the floor of the lighthouse balcony (before mending your roof).
 
 

 
Open the chest to find a shotgun and two shells.
 
 
The Fool (Day 4)
 
 

 
Grab the shotgun and the shells from the chest. Wait with the mending.
 
Shoot the seagull at the lighthouse balcony first.
 
 
Justice (Day 4)
 
 

 
You come face to face with the entity in the lighthouse. Do not shoot it. Run to the cellar instead.
 
 
The Empress / The Moon (Day 4: The Maze)
 
 

 
You awaken in a maze with a lantern lying on the floor. Leave it there.
 
The entity hunts you. Do not get hit, let alone get killed.
 
 
The High Priestess (Day 4: The Underground)
 
 

 
You come across a temple underground. There are four bonfires inside. Torch them.
 
 
 

Endings

 
The Devil – When you come face to face with the entity, just run for your life.
 
The Hanged Man – As the entity, do not follow your prey to the cellar – climb to the top of the lighthouse instead.
 
Judgement – When you come face to face with the entity, shoot it (with the shotgun).
 
 
The last achievement, Major Arcana, unlocks after getting all the others.
 
If not, start your adventure anew and step unto the pier once more.
 
That should do it.
 
 
Now, you rest in peace.
 
 

 
 
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