The following are known Action Replay Codes for Half-Life on SEGA Dreamcast (Dreamcast). These codes were also known as GameShark Codes and in most cases will work on both devices.

Device Compatibility: Action Replay & GameShark

Unlock Slow Motion
2C291B4D
F8FC3F7E

Unlock Alien Mode
2C291B65
F8FC3F7E

(M)
0E3C7DF2
1645EBB3
0C1AB027
F8A9CB9F

Unlock Invincibility
2C291B05
F8FC3F7E

Unlock Invisibility
2C291B35
F8FC3F7E

Unlock Xen Grav
2C291BED
F8FC3F7E

Unlock Inf Ammo
2C291B1D
F8FC3F7E

These codes have been collected from around the web and all credit goes to the original poster of the code. Notes associated with any code may be written by the original code creator. Some notes have been added or modified from their original source.

Do you know any additional codes for this game? Is there an error listed above? Let us know about it and we’ll update the list.

Code Indexes for SEGA Dreamcast

• Action Replay Code Index
• CodeBreaker Code Index
• GameShark Code Index

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