Here is the full list of all 40 Prince of Persia: The Forgotten Sands achievements worth 1,000 gamerscore.
Reach the thick of the battle.
Catch up to Malik.
Release Solomon's Army.
Close the fortress gates.
Reach the final fight.
Complete the Enemy Tides Challenge.
Find and break a sarcophagus.
Find and break every sarcophagus.
Purchase every item in the upgrade menu.
Break 100 vases and sarcophagi.
Kill 50 enemies in a row without being hit and without using upgrade powers or the Power of Time.
Kill 500 enemies with the sword.
Jump on enemies 30 times in a row without falling or using the Power of Time.
Knock down 5 enemies with one kick.
Wall run for a total of 1/2 mile (805 meters).
Move on solidified water for 1 minute without using the Power of Time.
Defeat Ratash in the Throne Room wihout taking any damage.
Finish off 10 enemies in a row using only the Aerial Slash.
Finish the final battle against Ratash without taking any damage.
Use the finishing lunge 20 times.
Perform 20 Aerial Slash attacks.
Finish 5 titans with the Aerial Slash.
Kick 20 enemies off of ledges.
Knock down 15 enemies using the aerial kick.
Defeat 30 enemies using the Power of Flight.
Defeat an enemy by doing a power attack on the fifth hit in a combo.
Upgrade one power to level 4.
Purchase your first upgrade.
Save the Prince's life by using the Power of Time.
Use the Power of Time 20 times.
Defeat 50 enemies using the Flame Trail.
Defeat 50 enemies while using the Stone Armor.
Defeat 50 enemies using the Ice Blast.
Defeat 50 enemies using the Whirlwind.