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.
Concatenate multiple stealth kills
Complete Chapter 13
Obtain all 'Yurei' medals
Obtain all 'Kami' medals
Obtain all 'Oni' medals
Complete Chapter 12
Unlock all Skills
Find all Scrolls
Complete Chapter 11
Perform an aerial kill from a 10m height
Complete Chapter 9
Complete Chapter 10
Complete Chapter 8
Use 'Shinen' to swallow 3 guards at the same time
Complete Chapter 7
Use an explosive light to kill a guard
Die. Again. And again.
Complete Chapter 6
Perform your first Shadow Kill
Get killed by an arrow while throwing a 'Kunai'
Perform a Ceiling Kill
Completer Chapter 5
Summon 100 shadows
Perform a Ledge Kill
Complete Chapter 4
Kill 100 enemies
Destroy a Light Orb
Complete Chapter 3
Make a guard suspicious 3 times in a row
Complete Chapter 2
Die while performing a stealth kill
Perform 100 Shadow Leaps
Unlock a Skill
Find a Scroll
Obtain a 'Kami' medal
Skip a cinematic
Complete Chapter 1
Obtain a ‘Yurei’ medal
Obtain a 'Oni' medal
Obtain all 'Oni' medals in 'Nightfall'
Recover all Nisshoku Daggers
Obtain all 'Yurei' medals in 'Nightfall'
Complete Nightfall: Chapter IV
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
Blind 4 or more enemies with a Shadow Grenade
Kill two enemies at once with the help of Twin Shadow (Single Player)