Here is the full list of all 32 Tomb Raider: Anniversary achievements worth 1,000 gamerscore.
Completed the game on Hard difficulty (includes Easy and Medium Game achievements).
Completed Lost Island without dying.
Completed Egypt without dying.
Collected the seals of Anubis, Horus, Isis, and Osiris without dying.
Completed Greece without dying.
Completed the Croft Manor Time Trial.
Completed all Lost Island Time Trials.
Completed all the Egypt Time Trials.
Complete all the Greece Time Trials.
Defeated the Twin Centaur Bosses without dying (Greece).
Completed the Hephaestus room in Greece without being struck by lightning.
Completed all the Peru Time Trials.
Completed Peru without dying.
Completed the Peru gear puzzle without dying.
Completed all the Peru Super Actions without fail (first try).
Completed all the Lost Island Super Actions without fail (first try).
Defeated Natla without dying (Lost Island).
Collected all the relics and artifacts in Lost Island.
Defeated the Torso Boss without dying (Lost Island).
Collected all the artifacts and relics in Egypt.
Collected all the artifacts and relics in Greece.
Collected all the artifacts and relics in Peru.
Completed all challenges in the Croft Manor.
Completed the game on Easy difficulty.
Completed the game on Medium difficulty (includes Easy Game achievement).
Completed the central shaft in the Lost Island without dying.
Completed all the Egypt Super Actions without fail (first try).
Collected the Uzi weapon.
Completed all the Greece Super Actions without fail (first try).
Collected the Magnum weapon.
Collected the Shotgun weapon.
Defeated the T-Rex without dying (Peru).