The following are known Action Replay Codes for Tomb Raider Starring Lara Croft on Nintendo Game Boy / Color (GB / GBC). These codes were also known as GameShark Codes and in most cases will work on both devices.

Device Compatibility: Action Replay & GameShark

Have Sun Amulet and Moon Amulet
0167B4C1

Have Skeleton Key
0169B1C1

Have Alter Key
0169B1C1

Have Rapid Bullets
01638dc1

Have Yellow, Red, and Blue Handle
01ffb6c1

Have Red and Blue Diamond
0163b2c1

Have Gold Bars
0163b3c1

Have Iris
0163b4c1

Have Snake Eye, Nightmare Stone, and Orb
01ffb5c1

Have Staff Segment 1
0163b7c1

Have Staff Segment 2, 3
01ffb8c1

Have Heavy Bullets
01638ec1

Infinite Health
01ff89c1

Infinite O2
01ff8ac1

Have Large Health Paks
0163acc1

Have Small Health Paks
0163adc1

Have Door Keys
0163aec1

Have Panel Peices
0163afc1

Have Dynamite
0163b0c1

Have Snake Key
0163b1c1