Here is the full list of all 34 Insanity's Blade achievements.
The taste of true defeat
Beat the game on Casual difficulty
Pay your dues to the zombie priests
Wow! 100% on all your saves!
Complete the Arcade adventure!
Get hugged by a crawler
Rip an arm off 'em!
Deliver a punishing ball kick!
Get all the pointy things!
Reach the max level!
You beat the game!
Collect all the questy things!
Bought the 6-way magic daggers!
Thurstan gets possessed
Beat a walking level without crouching.
Play co-op on the day of love
Get the Cock Puncher
Go corpse surfing
Play singleplayer on the day of love
Tear 'em in two!
Die in the water
Use a continue on Stage 0
Set a hostage free
Now you can throw daggers!
Throw 'em around!
Play within punching distance!
Skip the How To Play Video
Revisit the How To Play video
You are an ARCADE MASTER!
Upgrade Finn's axes to max level!
You like to live dangerously, no saves!
Go through HELL with no saves!
Hey! We thought you liked it rough!
Finish Stage 0 in Hell Mode