Full list of all 24 Sniper: Ghost Warrior achievements worth 1,000 gamerscore. It takes around 20-25 hours to unlock all of the achievements on Xbox 360.
Collected all secrets.
Finished game on Normal difficulty.
Act IV Completed.
Finished game on Easy difficulty.
Act III Completed.
30 enemies killed with browning gun.
Act II Completed.
5 High-Voltage cable lines broken.
100 headshots delivered.
2 enemies killed with one shot.
50 headshots delivered.
All enemies on riverside in "Weaken The Regime" level killed.
15 enemies killed in concentration mode.
Act I Completed.
2 enemies killed with one grenade.
10 enemies killed with throwing knives.
Enemy killed by the wall.
10 birds killed.
Finish the game on Hard difficulty.
Kill 250 people using pistol.(Multiplayer)
Kill 250 people using sniper rifle.(Multiplayer)
Kill 500 people using sniper rifle.(Multiplayer)
Kill 2000 people.(Multiplayer)
Win 50 rounds playing online.(Multiplayer)