Here is the full list of all 97 Slay the Princess achievements.
Kiss her
Work through some issues and learn to trust again.
Share a thorny prison
Bring the Thorn to Her
Abandon her in a thorny prison
Hand your power to a suspicious character.
It was in your nature
Leave a suspicious character in the basement
Directly attack a suspicious character
Bring the Witch to Her
It was in her nature
Fall for the rest of your life
Fight your foe unarmed and go the distance
Unleash the power of pacifism on your foe
Take the bait from your foe
Free someone who doesn't want to be freed
Successfully flee from a creature in its den
Strike the heart from the belly of the beast
Successfully take the fight to a creature in its den
Bring the Damsel to Her
Your love will set you free
Bring the Burned Grey to Her
Burn at the hands of a faded spirit
Slay an innocent
Bring the Moment of Clarity to Her
See what hides behind her mask
Bring the Prisoner's head to Her
Free a prisoner
Bring the Den to Her
Dodge a creature until you can dodge no longer
Fool a predator by faking your own death
Bring the Networked Wild to Her
Embrace your transformation
When taken against your will, deal with your enemy the only way you can.
There are worse fates to suffer than a broken heart
Slay the Princess
Bring the Razor's heart to Her
Allow a sharp foe to vanquish herself
Bring the Wounded Wild to Her
Some tears can never be mended
Freeze in front of a creature on your first meeting
Bring the Adversary to Her
Cannot die cannot die cannot die
Bring the Prisoner to Her
Become your own jailer
Bring the Fury to Her
Slay your better
Bring the Apotheosis to Her
Witness your better's ascension
Bring the Tower to Her
Pledge your loyalty to your better.
Have a voice ruin your happy ending
Attempt to Out-Wait Your Destiny.
Whatever it is, you'll face it together.
Slay the Princess, and make some enemies along the way
We Carve Meaning
Only new beginnings
Break the mirror without asking any questions.
Pick up a passenger and take her to her destination
Bring the Drowned Grey to Her
Drown at the hands of a faded spirit.
Dispatch a prisoner
Bring the Wraith to Her
When taken against your will, witness your enemy's freedom
Stuck in a dream without a stair to be seen
Bring the Beast to Her
Free a creature while under extreme duress
So have you become nothing once again
This is it
You don't know what you're doing
What can I do to make you stop?
Why have you come back?!
Bring the Razor (Full) to Her
Master yourself and vanquish a sharp foe.
You did it! You saved everyone!
Finish the Game. (The Good Ending doesn't count)
And at the end of that path is a cabin
Beget Strange Endings
Bring the Eye of the Needle to Her
All of this is you
Run out of questions
Lure an enemy to advantageous terrain and win
Return to your destined path, or face the consequences
Bring the Nightmare to Her
You've unraveled
Let your terrors loose upon the world
Bring the Deconstructed Damsel to Her
You've withered
It's all she wanted
Bring the Spectre to Her
You've grown
Take on a spirit and destroy it the only way you can.
There's no going back now
You'll know it when you see it.
Bring the Stranger to Her
It's you
When everything is possible, nothing is.