Full list of all 51 Aragami achievements. It takes around 15-20 hours to unlock all of the achievements in the base game on Windows.
The base game contains 39 achievements, and there is 1 DLC pack containing 12 achievements.
Obtain all 'Oni' medals
Unlock all Skills
Find all Scrolls
Complete Chapter 13
Obtain all 'Yurei' medals
Obtain all 'Kami' medals
Complete Chapter 12
Complete Chapter 11
Complete Chapter 10
Complete Chapter 9
Complete Chapter 8
Get killed by an arrow while throwing a 'Kunai'
Complete Chapter 7
Use an explosive light to kill a guard
Complete Chapter 6
Perform your first Shadow Kill
Perform a Ceiling Kill
Perform a Ledge Kill
Summon 100 shadows
Perform an aerial kill from a 10m height
Completer Chapter 5
Use 'Shinen' to swallow 3 guards at the same time
Die while performing a stealth kill
Die. Again. And again.
Kill 100 enemies
Concatenate multiple stealth kills
Obtain a 'Oni' medal
Skip a cinematic
Complete Chapter 4
Destroy a Light Orb
Complete Chapter 3
Make a guard suspicious 3 times in a row
Complete Chapter 2
Obtain a 'Kami' medal
Perform 100 Shadow Leaps
Unlock a Skill
Find a Scroll
Complete Chapter 1
Obtain a ‘Yurei’ medal
Recover all Nisshoku Daggers
Obtain all 'Oni' medals in 'Nightfall'
Blind 4 or more enemies with a Shadow Grenade
Complete Nightfall: Chapter IV
Obtain all 'Yurei' medals in 'Nightfall'
Obtain all 'Kami' medals in 'Nightfall'
Complete Nightfall: Chapter III
Complete Nightfall: Chapter II
Complete Nightfall: Chapter I
Kill 4 or more enemies at once with the Explosive Kunai
Kill two enemies at once with the help of Twin Shadow (Single Player)