Here is the full list of all 80 Dishonored Definitive Edition achievements worth 1,640 gamerscore.
You completed The Brigmore Witches in Low Chaos
You completed The Brigmore Witches without alerting anyone
You restored the Undine to working condition
You broke Lizzy Stride out of Coldridge Prison
You delivered (or attempted) the killing blow on Corvo
You completed The Knife of Dunwall in Low Chaos
You completed The Knife of Dunwall without alerting anyone
You completed The Knife of Dunwall without killing anyone
You obtained Delilah Copperspoon's identity from Thalia Timsh
You spoke with the statue of Delilah in Timsh's estate
You got the information you needed from the Rothwild Slaughterhouse
You completed the game in low chaos
You completed all missions after the prologue without alerting anyone
You completed the game
You saved Empress Emily Kaldwin
You deactivated at least 5 security systems on Kingsparrow Island
You completed all the Slackjaw side missions
You collected all the Sokolov paintings
You spared Daud’s life
You recovered your belongings
You neutralized all key targets using indirect means
You traveled 30 meters in less than 1 second
You brought about the Lord Regent's fall from grace by broadcasting his crimes
You completed the Boyle Estate mission without spoiling the party
You pickpocketed items worth a total of 200 coins
You acquired 15 equipment upgrades
You played from the first mission through Kaldwin's Bridge killing fewer than 10 characters
You abducted Anton Sokolov, Royal Physician
You got the Art Dealer's safe combination for Slackjaw, but robbed the safe first
You located Lady Emily Kaldwin, heir to the throne
After escaping prison, you completed a mission, not alerting anyone and killing less than 5 people
After escaping Coldridge Prison, you completed a mission without alerting anyone
You eliminated High Overseer Campbell
You protected Callista's uncle, Captain Geoff Curnow
You collected 10 bone charms
You escaped prison and navigated the sewers undetected
You escaped Coldridge Prison
Kill characters with each weapon and offensive gadget
Complete all missions after the prologue, alerting or killing no one but the key targets
Finish the game without purchasing any supernatural powers or enhancements, besides Blink
Kill an enemy using a Wall of Light
Assassinate 10 unaware enemies
Make others kill 5 of their own allies
Kill 5 characters with Drop Assassination
Complete the game without killing anyone
Cause 5 unintentional suicides
Stay in possession of others for most of a 3 minute period
Kill 4 enemies in less than 1 second using the crossbow
Kill 6 enemies in less than 1 second
After Coldridge Prison, elude 5 pursuers at once without killing them or leaving the map
Fight with 5 enemies at once, without any of them surviving
Assassinate the Lord Regent, Hiram Burrows
Grab a live grenade and use it to kill an attacker
Kill a tallboy with only your sword
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Find Emily's doll hidden in each of the 10 challenges
Perform a drop assassination of at least 150 meters in the Kill Cascade challenge
Complete Train Runner before the train arrives at the station
Finish Mystery Foe without using any active supernatural powers
Get to Wave 13 in Back Alley Brawl killing all combatants personally
In Bonfires, perform all the special combination jumps in 1 round
Complete Assassin's Run with 100% accuracy using only head shots
Find all of the collectable figurines in Burglar on Expert
Finish Chain Kill or Bend Time Massacre without failing any wave, including bonuses
Complete all Normal and Expert challenges with a 3-Stars rating
Purchase all of the Favors in The Knife of Dunwall
Complete The Knife of Dunwall in High Chaos
Attach an arc mine to a rat, resulting in a kill
Perform a drop assassination from atop the Empress statue in The Knife of Dunwall
Purchase at least 8 favors in The Brigmore Witches
Complete The Brigmore Witches in High Chaos
Complete The Brigmore Witches without killing anyone
Survive The Brigmore Witches in low chaos with 10,000 coins
Use an enemy lifted with Pull as a shield