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