Here is the full list of all 57 Star Wars Knights of the Old Republic II: The Sith Lords achievements.
Listen to HK-47's definition of love.
Reduce a companion's Influence to zero.
Recruit Mira
Teach the Handmaiden the ways of the Force.
Side with the Queen on Onderon
Recruit the Handmaiden
Complete the game on the Light Side
Reach maximum Light Side points
Complete the game on the Dark Side
Defeat Sion
Claim Darth Nihilus' mask.
Defeat Nihilus
Have your character replace any of the Sith Lords on the main menu screen.
Kill all the Jedi masters
Side with Vaklu on Onderon
Change your mind about siding with the Settlers at Khoonda
Side with the Settlers at Khoonda
Get the named Lightsaber crystal
Fill the Party Selection screen
Recruit the Disciple
Acquire all Light Side Powers
Complete the Mandalorian Battle Circle
Install HK-47's unique module
Learn how to kill Jedi from HK-47
Destroy Peragus Astroids
Learn Force Sight
Break Hanharr's spirit
Deduce G0-T0's identity
Beat the champ on Nar Shadaa
Convince the "champ" to lose the game without playing.
Win a Pazaak game with a full board
Convince Vogga the Hutt to sell fuel to Telos.
Acquire all Dark Side Powers.
Reach Player Level 30
Have 30 points in Treat Injury.
Recruit Hanharr
Have 30 points in Demolitions.
Have 30 points in Repair.
Repair the damaged droid on the Ebon Hawk
Learn Moving Meditation
Flee Korriban after fighting Sion
Get this by starting the "Trapped" Quest on Korriban.
Have 30 points in Stealth
Have 30 points in Computer Use.
Have Persuasion over 30
Loot a body on Korriban
Gain a Prestige class
Reach maximum Dark Side points
Contruct your first Lightsaber
Complete the Handmaiden Battle Circle
Collect 10,000 credits
Let the Sith destroy the Peragus Asteroids
Kill all Sith troopers before they can board the Ebon Hawk
Dance for Vogga
Get your first Dark Side points
Get your first Light Side points
Complete the Prologue