The following are known Action Replay Codes for Lady Sia on Nintendo Game Boy Advance (GBA).
These codes were also known as GameShark Codes and in most cases will work on both devices.

These codes are for the U.S. version of the game.

Master Code – Must Be On
730273dc
03f7c6e0
42a934db
12c9c314

Infinite Health
a63cdeb2
f3e28e96

Infinite Lives
6d2cbcf3
b7b5555f

Have Ring Power
c5f4eb82
78c6fb6d

Max Gems
66c0cc6d
130e65bb

All Prisoners Saved
bc5f7379
a9d71c3d

Press AR Button: Slow
dbba3a89
4cb74b94