The following are known Action Replay Codes for Tom and Jerry: Mouse Hunt 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
912e9ec2

P1 Quick Win
913230c9

P1 No Mice
910030c9

P2 Quick Win
91322fc9

P2 No Mice
91002fc9

Start On Last Level!
9117c9c2