The following are known Action Replay Codes for Sgt. Rock: On the Frontline 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

Stop Timer
01099fcb

Infinite Lives
0109b2cb

Max Score
010996cb
010997cb
010998cb