Precursor relic
Recursor relics are human-made artifacts designed to work just like the Pieces of Wden. Some of them can even work in conjunction with Isu-made Pieces of Eden. Two notable examples are Nicolas Flamel's Book of Abraham, and the Voynich manuscript,[1] which required unlocking by a precursor box.[2] Even the Head of Saint Denis works in conjunction with an Apple of Eden.
Examples of Recursor relics which do not work in conjunction with the Isu-made Pieces of Eden include, the Eagle of Suger, the Armor of Altair, the Mayan Armor and the Philosopher's Stone. Warren Vidic even created a prototype Piece of Eden which he used to implant a hidden impulse in Daniel Cross's mind, which would drive him to seek out the modern Assassin's mythical Mentor and slay him.
The Animus can also be considered a Recursor relic, given as how it was based on Isu technology.