The Great Disaster
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|The Great Disaster|
- "My name is Eriana-3, disciple of the Praxic Warlocks, marked by the Cormorant Seal. Survivor of the great disaster: the day we set out to retake our Moon, united in a host of thousands, and found ourselves outmatched by one Hive champion of unspeakable power."
- — Eriana-3
The Great Disaster was a battle fought between thousands of Guardians and the Hive to take control of the Moon.
- ""What madness is this!
"Lord Shaxx! The Consensus did not—"
"We barely eked out victory at Burning Lake. And now you think we're ready to attack the Moon?"
"Zavala! You can't think this is wise. We need to examine these swords, train against them—"
"This is a matter for the Consensus to decide, old friend.""
- — Grimoire: Raze-Lighter
Shortly after discovering the Hive during the Battle of Burning Lake, the Vanguard and the Consensus ordered a full-scale assault on the Moon to establish a beachhead for future plans of reclamation. Lord Shaxx, however, warned the Consensus that the Ascendant Swords carried by the Hive Knights were unlike any weapon he'd seen before, and that they should delay the attack. However, the Consensus and Vanguard went ahead with the battle plans anyways, confident in the Guardian's abilities to reclaim Luna.
- "I vividly remember the stories from that night. The sky burning green, the roar of thunder ripping through the darkness, and the Eater of Hope tearing through our ranks. Crota, the merciless Hive prince whose dark campaign to pursue the Traveler led to the slaughter of countless worlds—all in the name of his father, Oryx, the Taken King."
- — Eris Morn.
The Guardians who arrived fell by the hundreds, as leading the Hive army was the God-Prince Crota, an invincible Knight who devoured the Light of the Guardians. Mare Imbrium was one of the battlefields, as Crota led one thousand Knights against over five hundred Guardians, easily cutting through them. The legendary Titan Wei Ning was personally killed by Crota here. It was claimed the sky above the region "turned into green fire" and that the battle cracked open the surface of Luna itself.
During this campaign, an unknown Titan created the first Thunderlord, along with two other machine guns that came to renown: Nova Mortis and Abbadon. Though the Thunderlord survived, its counterparts were lost.
In the aftermath, the Vanguard scrambled to salvage the remaining resources of the battle as losses were nearly incalculable. They then classified the Moon as forbidden, and not to be visited unless absolutely necessary. Many Guardians were left behind on the Moon, left to fend for themselves as they were slowly picked off by the Hive or died of other causes. 
One of the survivors of the battle, Eriana-3, swore revenge against Crota and assembled a team of Guardians to enter the Hellmouth alone. Only Eris Morn survived that venture..
After the Great Disaster, the Vanguard and Consensus as a military structure essentially vaporized as trust in their leadership was called into question. Both the Vanguard and the Consensus dissolved into symbolic command as neither of them could get a grip on the remaining Guardians. As Aarach Jalaal puts it “Everyone is a rogue now. It is fashionable to be a rogue.”  The idea of the Vanguard as a commanding presence over all Guardians is completely defunct as the Vanguard struggles to even manage the practices done in the Crucible. . Due to this weakness, Zavala and Ikora both have considered the dissolution of the Vanguard as a structure completely. 
The Guardians and Culture
After the Great Disaster, Guardian culture took a sharp turn towards selling themselves for the highest bidder. Many people from the Drifter, to Calus, to Petra, and even Vance have noted that Guardians are unusually willing to do anything for a shiny new toy. The Drifter has had many Guardians join him on his escapades and even butted heads with Emperor Calus as the two fought over Guardian loyalty.  In a discussion with Petra, Variks says, "Guardians desire many things. Glory. Honor. Treasure."  Brother Vance has also said that "They're so eager to tear each other apart for guns and cloth."  Many guardians have fallen for these schemes and plots, ranging from Katabasis who died for Calus to Sola Scath who fell to Darkness.
It also did not help that due to the loss of so many figurehead Guardians like Wei Ning, there were very few elders left to teach the younger generation how to fight. This then resulted in the extremely close Battle of the Twilight Gap after which Shaxx left the battlefield in order to watch over the Crucible so that he could train the next generation of battle-hardened Guardians himself. 
Many civilians also feel distrustful of the Guardians due to their lack of command. Many of them wonder if Guardians are even partial to their survival. Especially during the return of the Pyramids, citizens have even been noted to attack Guardians. 
List of appearances
- Destiny (First mentioned)
- The Dark Below (Mentioned only)
- Destiny 2
- Forsaken (Mentioned only)
- Black Armory (Mentioned only)
- Joker's Wild (Mentioned only)
- Shadowkeep (Mentioned only)
- Beyond Light (Mentioned only)
- The Witch Queen (Mentioned only)
- ^ Bungie (2015-9-15), Destiny: The Taken King, Activision Blizzard, Grimoire: Crota's End
- ^ Bungie (2015-1-23), Destiny: Activision Blizzard, Grimoire: Moon
- ^ Bungie (2015-1-23), Destiny: PS3, Activision Blizzard, Grimoire: Ghost Fragment: Warlock 2
- ^ Bungie (2015-1-23), Destiny: Activision Blizzard, Grimoire: Nova-Mortis
- ^ Bungie (2015-1-23), Destiny: Activision Blizzard, Grimoire: Ghost Fragment: The Ocean of Storms
- ^ Bungie (2015-1-23), Destiny: Activision Blizzard, Grimoire: Ghost Fragment: The Ocean of Storms2
- ^ Bungie (2015-1-23), Destiny: Activision Blizzard, Grimoire: Nova Mortis
- ^ Bungie, (3/2/2019), Narrative Preview - Praxic Order
- ^ Bungie, https://www.ishtar-collective.net/interactions/commander-zavala-defender-of-light
- ^ Bungie (2019-3-5), https://www.ishtar-collective.net/entries/instability#book-stolen-intelligence
- ^ Bungie (2019-6-4), https://www.ishtar-collective.net/entries/penumbral-cloak?highlight=penumbral+cloak
- ^ Bungie (2019-4-12), https://www.ishtar-collective.net/cards/challenge-of-the-elders?highlight=Challenge+of+the+Elders
- ^ Bungie (2020-3-10), https://www.ishtar-collective.net/entries/chapter-5-ambition#book-trials-and-tribulations
- ^ Bungie (2014-9-9), Destiny, PlayStation 4, Activision Blizzard, Grimoire: Crucible Handler
- ^ Bungie https://www.ishtar-collective.net/records/citizens-of-the-city