What is the name of the powerful artifact sought in the first Assassin's Creed?

The powerful artifact sought in the first Assassin's Creed is the Apple of Eden.

The Apple of Eden is one of the fictional Pieces of Eden, technologically advanced artifacts created by the precursor civilization known as the Isu. In the first game, Altaïr and several factions pursue an Apple because it can influence perception and control people who are exposed to its power.

The artifact's spherical appearance echoes the traditional image of an apple, but its role is science fiction rather than ordinary mythology. The series later reveals that Pieces of Eden were created by the Isu and survived into human history.

Other named artifacts include the Staff of Eden, the Sword of Eden, and the Shroud of Eden. They are related objects in the same fictional artifact family, not alternative names for the Apple in the first game's story.