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
Destroyed the Red Judge
Destroyed the Red Judge aspect in Acheron
Destroyed the Red Judge aspect in Nihil
Destroyed the Red Judge aspect in Gehenna
Destroyed the Red Judge aspect in Incaustis
Soared (Dash + jump) 100 times
Obtained all weapons
Destroyed the Red Judge aspect in Yhelm
Died in a Chaos Crystal explosion
Killed 50 Behemoths
Destroyed the Red Judge aspect in Stygia
Killed 8 enemies in 4 seconds
Got 666 kills (game total)
Achieved the top result in a Torment
Completed a Torment
Destroyed the Red Judge aspect in Voke
Reached Hit Streak: 20
Reached Hit Streak: 10
Multi-killed 2 enemies
Reached Hit Streak: 35
Reached Hit Streak: 50
Completed all Torments
Never hit off-beat in a Hell
Killed 25 enemies while maintaining a Hit Streak
Killed two Seraphs in one attack
Cleared a Hell using only Paz
Killed a Judge's Aspect with Terminus