Quest RPG: Brian's Journey was released on the Game Boy Color. It is a port of the Nintendo 64 game, Quest 64. The game is not a direct port, some areas are different as well as some text and bosses. It was released February 3rd, 2000. Originally released under the name "Quest RPG" then was later changed to add the "Brian's journey" at the end of the title.
The plot is a close replica of the original story. The playable character is an apprentice mage named Brian. Brian sets off to find his father who has left the monastery of the mages—the player learns later that his father is looking for a thief who has stolen the "Eletale Book". The player must also collect elemental amulets, which have been hoarded by powerful criminals and are integral in the defeat of the game's final boss.
Source: Wikipedia, "Quest RPG: Brian's Journey", available under the CC-BY-SA License.