Here is the full list of all 42 Mini Knight achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Go Left
First Restart
Game Over
First Death
12 Lvl completed
End Game
Music 12
Last Step
11 Lvl completed
Music 11
10 Lvl completed
Music 10
9 Lvl completed
Music 9
8 Lvl completed
Music 8
7 Lvl completed
Bandit 3 Dead
Music 7
6 Lvl completed
Music 6
Middle Game
5 Lvl completed
Music 5
4 Lvl completed
Music 4
1/3 of the game
3 Lvl completed
Music 3
2 Lvl completed
Music 2
1 Lvl completed
Bandit 2 Dead
Bandit 1 Dead
Go Right
Jump
Pause 2
Fall
Pause
Mute
Music 1
Start Game