The Mask of the Ibis is a recurring Helix Rift Event in Assassin's Creed: Rebellion that originally lasted from April 3–7, 2019. It comprises of five missions set in Egypt shortly after the founding of the Hidden Ones, and follows Bayek of Siwa and Kensa as they hunt down the Ibis Reborn, a mysterious cult leader who sought to use Isu artifacts to seize power over Egypt.
Successful mission synchronization gives players Data Nodes which unlock various reward tiers based on the total Nodes collected, with the top tier granting players the ability to play Bayek in future missions; a sword, set of medium armor, and accessories scaled to one's Brotherhood level; and codex. Players can earn extra Nodes if they use one or more preset Sync Bonus Heroes.
Egypt, 46 BCE
In 46 BCE, soon after the foundation of the Hidden Ones by Bayek of Siwa, rumors of a mysterious individual claiming to be the resurrected form of The Ibis, Medunamun, began to spread.
Reports from various Hidden Ones spoke of a new cabal of fanatical cultists, formed from the straggling remnants of the Order of the Ancients. They were rallying behind their miraculously returned leader and were absolutely devoted to carrying out his whim.
Deeply troubled by the news, Bayek feared some new power might be within the Order's grasp, and decided to lead the Hidden Ones in a search of this new "Sect of The Ibis Reborn".
This Sect was young, and thus difficult to find, but also vulnerable. The Hidden Ones were able to identify a member of the Sect and they tracked him to a remote temple in Haueris Nome in Lower Egypt. They closed in on the location, and prepared to return Medunamun's heart to Osiris' scales.
With the power of the Animus simulation, it is now your turn to experience the Hidden Ones' hunt of the Ibis Reborn...
Chapter 1 - Haueris Nome
Chapter 2 - White Desert
Chapter 3 - Giza