Here is the full list of all 40 Prince of Persia: The Forgotten Sands achievements worth 1,000 gamerscore.
Closed the fortress gates.
Used aerial kick 15 times.
Defeated 50 enemies using the Whirlwind.
Completed the Enemy Tides Challenge.
Defeated 50 enemies using the Ice Blast.
Purchased every upgrade.
Complete the game.
Reached the final fight.
Razia becomes part of sword.
Upgraded one power to its highest level.
Arrived in Razia's city.
Killed 50 enemies in a row without taking any damage.
Suffered defeat at Malik's hands.
Defeated 50 enemies while using the Stone Armor.
Defeated 30 enemies using the Power of Flight.
Kicked 20 enemies off of ledges.
Killed 500 enemies using the sword.
Defeated an enemy with a power attack at the end of a combo.
Defeated Ratash?
Defeated 50 enemies using the Flame Trail.
Used the Power of Time 20 times.
Found a sarcophagus.
Broke 100 things. (Feel better?)
Wall run for a total of 1/2 mile (805 meters).
Used the upgrade menu.
Used the finishing lunge 20 times.
Saved the Prince's life by using the Power of Time.
Discovered the true nature of Solomon's army.
Caught up to Malik.
There's no turning back now!
Knocked down 5 enemies with 1 kick.
Find and break every sarcophagus.
Jump on enemies 30 times in a row without falling or using the Power of Time.
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.
Secret
Perform 20 Aerial Slash attacks.
Finish 5 titans with the Aerial Slash.