A Gnosis (Chinese: 神之心 Shén Zhī Xīn, "Heart of God") (plural Gnoses) is an item used by The Seven to directly tap into energy from Celestia, and is proof of their status as an elemental Archon. It is unknown whether gods before The Seven possessed Gnoses.
Taking on a physical appearance reminiscent of a glowing chess piece, they otherwise reside within the Archon's body and can either be forcefully removed through the powers of another archon (as with the powers bestowed upon the Eleven Fatui Harbingers by the Tsaritsa) or willfully materialized and given away by the Archon themselves.
The Tsaritsa seeks to collect the Gnoses of all of the Seven for reasons yet unknown, and is currently in possession of three: her own Cryo Gnosis, Venti's Anemo Gnosis (taken through force by La Signora), and Zhongli's Geo Gnosis (obtained peacefully through a contract).
All that is currently known about the uses of a Gnosis is that it is used to resonate with Celestia directly, and that it grants its respective archon the "divine ability" to defend their nation. However, archons do not seem to be wholly reliant on Gnoses for power, unlike mortals who can only manipulate elemental energy by harnessing a Vision. Venti and Zhongli are capable of using their elemental abilities in battle during their respective Story Quests, both of which are set after they lose their Gnoses.
While the archons do not seem to depend on Gnoses to harness elemental energy, their powers are still limited without them; Zhongli states that the "power of the Geo Archon" is required to create Mora, and indicates that the Golden House will have to temporarily close since he can no longer do this. His Voice-Over lines also indicate that he lost a significant portion of his power after relinquishing his Gnosis, but still retained enough power to be able to fight.
In some cases, archons have other means of resonating with Celestial energy, independent of their Gnoses. Venti harnesses the power of the massive tree at Windrise twice; first was to expunge the abyssal magic that poisoned him via Dvalin, and the second was to heal himself after having his Gnosis taken by Signora.
- So far both Gnoses that have appeared in the story were styled after a specific type of chess piece: The Anemo Gnosis standing in for the queen, while the Geo Gnosis stood in for the rook. It is interesting to note, that the standard (western) chess game has only 6 distinct pieces (pawn, rook, knight, bishop, queen and king) which would be one short for a full set of all the Seven's Gnoses.
- In Gnosticism, gnosis is a term used for wisdom, knowledge, or insight into divine nature. It is through gnosis that one can transcend the material realms controlled by the seven archons and enter the supercelestial realm of Ogdoad.
- The Chinese term for Gnosis, 神之心 Shén Zhī Xīn, "Heart of God", is similar to the term for Visions (Chinese: 神之眼 Shén Zhī Yǎn, "Eye of God"). Both of them are called 魔力器官 "magical organs [apparatuses]", which was translated as "internal magical focus" in English.