Unlockables - Complete each achievement to get the allotted gamerscore.

4 8 15 16 23 42 (15) Photograph numbers on sealed hatch
815 (20) Discover all the memories in Flashback 1

A Turn of the Screw (10) Photograph A Turn of the Screw

Beam of light (20) Photograph beam of light coming from the hatch
Behind the glass (20) Discover all the memories in Flashback 3
Behind the wall (100) Complete Episode 5
Blackmailer (15) Convince Locke to help
Boom boom (10) Open the secret door
Button pusher (15) Enter the numbers

Castaways' Treasures (10) Photograph: 1- Kate's plane 2- Charlie's guitar 3- Locke's wheelchair
Crash survivor (25) Complete Episode 1

Desmond's Past (10) Photograph: Kelvin's jump suit Medical cabinet with vaccines Desmond's mural
Dharma Ride (15) Photograph Dharma van

Hero's hero (25) Save Jack

Identity crisis (30) Discover all the memories in Flashback 4
Into the hatch (75) Complete Episode 4

Locate the cockpit (25) Complete Episode 2

Mapping the Island (10) Photograph: 1- Blast door map 2- Blast door map for the hidden entrance 3- Sayid's cable map
Medical Station (20) Photograph Medical Station emblem

Pearl Station (20) Photograph Pearl Station emblem
Persephone (30) Discover all the memories in Flashback 5

Radzinsky (15) Photograph bloodstain on the Swan ceiling

Save the castaways (15) Prevent the fuel leak from igniting
Showdown (10) Successfully confront Beady Eyes
Slave (15) Photograph skeleton in Black Rock
Sweet memory (20) Discover all the memories in Flashback 2

The way home (200) Finish the game
Through the Flame (125) Complete Episode 6

Via Domus (50) Complete Episode 3

Whatever it takes (30) Discover all the memories in Flashback 6