Unlock the following costumes by performing the corresponding tasks:

COSTUME - HOW TO UNLOCK
Lara's Biker outfit - Score 1,900,000 points in single player mode.
Lara's Heavy Jungle outfit - Complete the game.
Lara's Jungle outfit - Score 1,410,000 points in single player mode.
Lara's Legends outfit - Defeat Xolotl.
Lara's Doppelganger outfit - Score 2,400,000 points in single player mode.

ACHIEVEMENT - HOW TO UNLOCK
A Friend in Need - Play co-op mode.
Beat a Better Mousetrap - Activate all of the spikes at once in the Spider Tomb spike field.
Breadwinner - Earn the top score objective in any level.
Instant Sushi - Vanquish the summoned beast in the watery depths.
Jump Jump - Jump from Totec's shield while he is jumping.
Leap of Faith - Catch Totec with the grapple while he is jumping over a death fall.
Overachiever - Complete any level-specific Reward Challenge.
Return to Sender - Reflect an enemy's projectile back to him using Totec's shield.
Seeing Red - Collect all 10 red skulls in any single level.
Three birds, one stone - Kill 3 enemies with one bomb.
Tomb Raider - Collect all relics, artifacts and weapons.
Vanquish Xolotl - Regain the Mirror of Smoke.