Full list of all 80 Dishonored achievements worth 1,640 gamerscore. It takes around 25-30 hours to unlock all of the achievements in the base game on Xbox 360.
The base game contains 50 achievements worth 1,000 Gamerscore, and there are 3 DLC packs containing 30 achievements worth 640 Gamerscore.
You completed all missions after the prologue, alerting or killing no one but key targets
You completed all missions after the prologue without alerting anyone
You completed the game without killing anyone
You finished the game without purchasing any supernatural powers or enhancements, besides Blink
You played from the first mission through Kaldwin's Bridge killing fewer than 10 characters
You protected Callista's uncle, Captain Geoff Curnow
You completed the game in high chaos
You caused 5 unintentional suicides
You killed 6 enemies in less than 1 second
You grabbed a live grenade and threw it back, killing an attacker
You assassinated 10 unaware enemies
You stayed in possession of others for most of a 3 minute period
You escaped prison and navigated the sewers undetected
You completed the game in low chaos
You completed the game
You saved Empress Emily Kaldwin
You deactivated at least 5 security systems on Kingsparrow Island
You completed all the Granny Rags side missions
You collected all the Sokolov paintings
You completed all the Slackjaw side missions
You spared Daud’s life
You killed characters with each weapon and offensive gadget
You killed 5 characters with Drop Assassination
You recovered your belongings
You assassinated an assassin
You neutralized all key targets using indirect means
You assassinated the Lord Regent, Hiram Burrows
You brought about the Lord Regent's fall from grace by broadcasting his crimes
You completed the Boyle Estate mission without spoiling the party
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 killed a tallboy using only your sword
You made others kill 5 of their own allies
You killed 4 enemies in less than 1 second using the crossbow
You acquired 15 equipment upgrades
You abducted Anton Sokolov, Royal Physician
You killed an enemy with the Wall of Light
You reached the top of Kaldwin's Bridge
You got the Art Dealer's safe combination for Slackjaw, but robbed the safe first
You pickpocketed items worth a total of 200 coins
You killed Morgan Pendleton with steam
You took possession of a fish
You located Lady Emily Kaldwin, heir to the throne
You collected 10 bone charms
You traveled 30 meters in less than 1 second
You used a rat tunnel
You eliminated High Overseer Campbell
You fought 5 enemies at once and none of them survived
After Coldridge Prison, you eluded 5 pursuers at once without killing them or leaving the map
You escaped Coldridge Prison
You completed Train Runner before the train arrives at the station
You performed a drop assassination of at least 150 meters in the Kill Cascade challenge
You finished Mystery Foe without using any active supernatural powers
Find Emily's doll hidden in each of the 10 challenges
Complete all Normal and Expert challenges with a 3-Stars rating
Get to Wave 13 in Back Alley Brawl killing all combatants personally
Find all of the collectable figurines in Burglar on Expert
Complete Assassin's Run with 100% accuracy using only head shots
In Bonfires, perform all the special combination jumps in 1 round
Finish Chain Kill or Bend Time Massacre without failing any wave, including bonuses
You completed The Knife of Dunwall in High Chaos
You performed a drop assassination from atop the Empress statue in The Knife of Dunwall
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 caused a death using an arc mine and a rat
You purchased all of the Favors in The Knife of Dunwall
You got the information you needed from the Rothwild Slaughterhouse
You completed The Brigmore Witches in Low Chaos
You completed The Brigmore Witches without alerting anyone
You completed The Brigmore Witches without killing anyone
You purchased at least 8 favors in The Brigmore Witches
You completed The Brigmore Witches in High Chaos
You survived The Brigmore Witches in low chaos with 10,000 coins
You used an enemy lifted with Pull as a shield
You restored the Undine to working condition
You broke Lizzy Stride out of Coldridge Prison
You delivered (or attempted) the killing blow on Corvo