The following are known Action Replay Codes for Skies of Arcadia 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

Aika - LV99
DDA4D6B9
00000063

Vyse - LV99
B2BA6FEB
00000063

Aika - Replenishing HP
8B735866
270F270F

Vyse - Replenishing HP
7B350664
270F270F

Aika - 99 MP
DDB896B9
00006363

Vyse - 99 MP
9CC81F91
00006363

Loads of Gold
EFE7CDF2
3B9A9CFF