The following are known Action Replay Codes for The Legend of Zelda: Oracle of Ages 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

Max Health
9140aac6

Infinite Health
9140abc6

Invincible
91152bd0

Have Master Sword
9103b2c6

Have All Secondary Items
91ff9fc6
91ffa0c6
91ffa1c6
91ffa2c6
91ffa3c6
91ffa4c6
91ffa5c6

Have All Essences Of Ages
91ffbfc6

Infinite Rupees
9109aec6
9199adc6

Infinite Bombs
9110B0C6

Have Mirror Shield
9103AFC6

Have Power Glove
9102B8C6

Have Tune of Ages on Harp of Ages
9103B7C6

Infinite Ember Seeds
9199B9C6

Infinite Scent Seeds
9199BAC6

Infinite Pegasus Seeds
9199BBC6

Infinite Gale Seeds
9199BCC6

Infinite Mystery Seeds
9199BDC6

Have All Dungeon Maps
01FF86C6
01FF87C6

Have All Compasses
01FF84C6
01FF85C6

Have All Boss Keys
01FF82C6
01FF83C6

Access The Advance Shop
01EA14CF

Infinite Rock Currency
0163AFC6

All Pieces of the Heart
0106ACC6

Infinite Magic Fire Powder
0109BCC6

Mega Jump
019014D0

Have Mermaid Suit
010CA3C6