Blackthorne Gameshark Codes (USA)
This page contains Gameshark cheat codes for Blackthorne (USA). If you're playing on an emulator you can usually input codes very easily by accessing a tab off the top of the toolbar. Anyone playing on a physical Gameboy will need to purchase a physical Gameshark device to use these codes.
If you're using an emulator and still can't figure out how to setup these codes, you're in luck! There's two common emulators for GBA games, the mGBA and VisualBoy Advance. Follow the link provided for the emulator you're using to be taken to a guide explaining how to get these codes working.
Unlimited Health: 03000FC8 0000000C
Invulnerable to Guns: 03001018 00000044
Max Weapon Upgrade: 0300021C 00000003
Have Bridge Key: 03001881 00000007
Have Fire Bomb: 0300187B 0000000A
Have Heal Potion: 0300187F 00000004
Have Hover Bomb: 03001879 00000005
Have Iron Key: 03001885 00000002
Have Levitator: 03001881 00000006
Have Remote Wasp: 0300187D 00000008
If any of these codes do not work for you, please leave a comment below.