Here is the full list of all 18 The World After achievements.
You're ready to start your adventure!
You've unlocked the suitcase!
You've found all of Marc's bottles!
You're a true shadow hunter!
You've opened the gate!
You've taken the map from Julie!
You've successfully crafted the gel!
You've unlocked the secret log!
You've waited long enough to witness something that can't be unseen...
You've completed the Visual Novel!
At least you've tried.
A brave new world.
Congratulations !
You've been quite annoying!
Try again.
Got yourself a gun!
You didn't take the gun.
You got the best possible score in the retro-filter DLC!