Here is the full list of all 28 Metal: Hellsinger achievements. It takes around 5-6 hours to unlock all of the achievements on Windows.
Died 20 times
Died in a Chaos Crystal explosion
Cleared a Hell using only Paz
Destroyed the Red Judge
Soared (Dash + jump) 100 times
Completed all Torments
Destroyed the Red Judge aspect in Acheron
Killed a Judge's Aspect with Terminus
Destroyed the Red Judge aspect in Nihil
Killed two Seraphs in one attack
Destroyed the Red Judge aspect in Gehenna
Destroyed the Red Judge aspect in Incaustis
Obtained all weapons
Destroyed the Red Judge aspect in Yhelm
Never hit off-beat in a Hell
Reached Hit Streak: 50
Reached Hit Streak: 35
Killed 25 enemies while maintaining a Hit Streak
Killed 50 Behemoths
Got 666 kills (game total)
Killed 8 enemies in 4 seconds
Destroyed the Red Judge aspect in Stygia
Reached Hit Streak: 20
Achieved the top result in a Torment
Completed a Torment
Destroyed the Red Judge aspect in Voke
Multi-killed 2 enemies
Reached Hit Streak: 10