Cheat list
By completing the game on Easy difficulty, you will unlock the ability to use the following cheats: Unlimited breath No textures Glasses

Unlockable: Time Trial Secrets
Set the game difficulty to "Time Trial" and complete the following trials to earn the unlockable extras:

Unlimited 50 Cal. Pistol	Complete Peru
Unlimited SMG + Unlimited Health	Complete Egypt
Golden Shotgun + SMG	Complete Lost Island

Unlockable: Secret Costumes
Collect relics in the following areas to unlock these secret costumes:

Camo Costume	Temple of Kharmoon
Catsuit Costume
Croft Manor Costume	Midass Palace
Golden Costume	Midass Palace
Doppelganger Costume	Nattas Mines
Tomb Raider 1 Costume	Lost Valley
Tomb Raider Legend Costume	Mountain Caves
Tomb Raider 2 Swimsuit	Great Pyramid