So before anything else is said, a basic understating of the Vex goal is required. The Vex are searching for what they call "an emperor to all outcomes." This means they want to have something in place so that no matter what happens they have some kind of response that ultimately leads to a Vex victory, or at the very least their continued survival. To do this they gather as much data as they can, use that data to simulate every possible scenario, and then construct a specialized project for each possible scenario. The Black Garden and the Vault of Glass are two such projects built to fulfill two separate victory conditions. The first known fireteam to enter the Vault was composed of at least 3 known guardians. It is theoretically possible there were more and they were simply deleted from time and memory, but only Kabr, Praedyth, and Pahanin are known to have explored the Vault. Praedyth eventually found himself removed, locked out of our reality in a Vex cell apart from time itself. He was later used as bait, to manipulate future generations of guardians into cleansing the Vault of Oryx's power during the Taken Wars. Pahanin is the only one of the original fireteam to have survived the encounter, but he went mad as a result of his experience. When outside he eventually built the custom machinegun Super Good Advice, and installed an AI within it. He convinced himself that as long as another mind was always there to perceive him, the Vex could not delete him since something else recognized his existence. He was later killed by the renegade guardian Dregen Yor on Mars. Kabr was consumed by the Vault, but also reached a fundamental understanding of it. The exact sequence of events remains unknown, but at some point he killed a Gorgon and drank Vex fluid, which he claimed tasted of the sea. One of his last actions was to forge the Aegis from the remnants of the Gorgon he destroyed and infused it with his own light. It is this sacrifice that later allowed future guardians to challenge Atheon and defeat him in the Glass Throne. From what we can tell, the Vault is most likely the culmination of Vex efforts to understand and replicate a Hive Throne World based on what Quria, Blade Transform learned during his war with Oryx before being defeated. The Vex want to use the vault to establish themselves as a fundamental rule of existence. All the various mechanics we see throughout the raid are the result of the Vex possessing or attempting to gain control over the nature of reality itself. The Templar's Ritual of Negation and Oracles are one such example of this control. The Oracles are able to tag enemies and then the Templar uses the ritual to delete what the Oracles tag from existence. Put another way, the Oracles decide how the Vex want to change and shape reality and the Templar makes that reality so. The Gorgons have a similar function but it works slightly different. Gorgons can both tag and delete, but they must physically see what they want to change while the Oracle-Templar combo do not. As previously stated, the Aegis was created by Kabr, the Titan who led the original failed raid of the vault. He built it by merging his dying light and what remained of his ghost with the body of a Gorgon he destroyed. This allows future Guardians to channel and use light to shape reality within the Vault. It is this shaping of reality that allows the Relic to destroy the Templar's otherwise impenetrable shield. Since it is made of a Gorgon, and therefor tied to the Vault, the Vex can't destroy of delete it. The final area is the Glass Throne and is the seat of Atheon, Time's Conflux. All time bends around itself and meets in this place. Precursor, Descendent, and modern Vex all exist because the future, past, and present all exist here. The timegates in the room don't lead to "Mars" and "Venus" as most call it, but to past and future versions of the Vault. Two relics exist here for a short while because you pull one from a past version of the Vault and one from a future version of the Vault. Atheon teleports you to separate you so that you can be killed individually. We are saved again by the Aegis because Kabr made it so it is a fundamental rule within the Vault. Why exactly entering the future and past causes a blinding effect is unknown but it definitely has something to do with one of Kabr's final quotes. "Bind yourself to the shield. Bind yourself to me. And if you abandon your purpose, let the Vault consume you, as it consumed me." It exists in the past and future and we use it to pull ourselves back into the present. When we do so after being teleported it activates the "Time's Vengeance" effect. We do not know exactly "Time's Vengeance" is but the leading theory is that bringing either the past of future Aegis into the present causes all timelines to temporarily and partially merge. Our weapons do so much extra damage because for a brief time it isn't just our 6 man fireteam doing damage, but every guardian that ever has and ever will reach Atheon from every timeline coming together. [b][i][u]NOTE:[/u][/i][/b] For those interested in reading more, this post is just my small contribution to a more expansive project within the lore community. Those interested in reading more should refer to the link below. https://www.bungie.net/en/Forum/Post/206388637/0/0