Here is the full list of all 33 Prisoner achievements.
Complete the game 10 times
Complete all achievements
Complete the game 5 times
Complete the game
Complete Uber Complex
Complete Trial of Darkness
Complete the game with 2 active trials
Complete the game with 3 active trials
Complete the game with 4 active trials
Complete the game with 5 active trials
Pass 500 rooms
Reach the 100 rooms in Endless Complex
Complete Trial of Death
Unlock Stage 6
Find 25 Secret Rooms in the New Complex
Pass 250 rooms
Pass 25 extra rooms
Activate the 50 Mystery Mechanisms
Reach the 50 rooms in Endless Complex
Reach the 75 rooms in Endless Complex
Collect all character skins
Unlock Stage 5
Complete Trial of Time
Unlock Stage 4
Complete Trial of Life
Pass 100 rooms
Reach the 25 rooms in Endless Complex
Collect 6 character skins
Find 10 Secret Rooms
Find the secret way in extra room
Activate the Mystery Mechanism
Collect 3 character skins
Find a Secret Room