Here is the full list of all 42 Lies of P achievements. It takes around 60-80 hours to unlock all of the achievements on Windows.
Collect and play all records.
Find out about the last story of Antonia.
Find out about the last story of Eugénie.
Learn all gestures.
Collect all special weapons.
Find out about the last story of Sophia.
[Rise of P] Reach the ending.
Kill the Nameless Puppet.
Play a perfect tune on the piano at Hotel Krat.
Find out about the last story of Geppetto.
[Real boy: They all lived happily ever after] Reach the ending.
Find out about the last story of Simon Manus.
Kill the Awakened God Simon Manus.
Find out about the last story of Venigni.
Collect all normal weapons.
Kill Laxasia the Complete.
Discover all Trinity Sanctums.
Strengthen a special weapon to its max level.
Kill the Black Rabbit Brotherhood.
Strengthen a normal weapon to its max level.
Collect all Legion Arms.
Activate P-Organ to Phase 5.
Kill the Corrupted Parade Master.
Modify a Legion Arm to its max level.
Kill the Puppet-Devouring Green Monster.
Kill Champion Victor.
Kill all types of Dimensional Butterflies.
Kill Romeo, King of Puppets.
Harvest Gold Coin Fruit.
Kill the Eldest of the Black Rabbit Brotherhood.
Kill the Fallen Archbishop Andreus.
Kill King’s Flame, Fuoco.
Kill the Scrapped Watchman.
Try to assemble a weapon.
Kill a Stalker.
Destroy an enemy’s weapon with a perfect guard.
Tell a lie in front of Hotel Krat Entrance.
Kill the Parade Master.
Repair a Stargazer.
Deliver a successful Fatal Attack.
[Free from the puppet string] Reach the ending.
Decipher all cryptic vessels and claim the rewards.