Here is the full list of all 42 The Last Hero achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Mute
Go Left
Go Right
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
Bandit 3 Dead
7 Lvl completed
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
Bandit 1 Dead
Bandit 2 Dead
First Restart
Game Over
First Death
Pause 2
Pause
1 Lvl completed
Jump
Music 1
Fall
Start Game