Destiny 2 has been evolving constantly over the years thanks to its many gameplay changes and all the new storylines coming through Seasons and annual expansions, like last year's Beyond Light or the upcoming The Witch Queen. Four years after its release, Destiny 2 is still very relevant thanks to all these additions, but starting with Beyond Light, yearly DLCs started to come at the price of older content. In fact, last November, Bungie introduced the Destiny Content Vault in order to remove old locations and campaigns to reduce the impact of file size on loading times and storage space, which received mixed opinions from the community due to some plotlines being lost for good.
The story of Destiny and Destiny 2 is a huge continuum, so missing out on the first game can in and of itself mean that new players are not fully up to date with what's going on prior to The Witch Queen. However, with the cuts to Destiny 2's content, this is even more of a problem if players didn't get a chance to complete old campaigns and experience planets like Titan, Io, Mars, and Mercury. As such, it shouldn't come as a surprise that many plot developments within Destiny 2 cannot be experienced any longer, even though some of them were pivotal to the game's storytelling - and, in some cases, still are.
Destiny 2's Red War Campaign and Its Consequences
The Red War campaign was the so-called vanilla Destiny 2, as it was the one and only campaign to play through at launch, and it comprised several bite-sized chapters scattered across Sol. The main plot point, and also the inciting incident of Destiny 2 as a whole, is that Dominus Ghaul successfully captured the Traveler in order to deprive humanity of its Light, but also found a way to acquire it for himself. Ghaul also held the Speaker captive and questioned him about the Traveler and the Light, eventually asking him how he was meant to obtain the Light.
The Guardian regained its Light thanks to shards of the Traveler found in the EDZ, getting visions of Light and bursts of power whenever they found one. After reclaiming a foothold within the EDZ, the Guardian eventually went to Titan to help Zavala and Commander Sloane obtain a Golden Age CPU from the Hive, helping them learn more about Ghaul's Almighty - a weapon capable of destroying the Sun and Sol with it. Thus, players were tasked with finding Cayde-6 on Nessus, who tried to steal a Vex teleporter with the help of a Golden Age malfunctioning AI called Failsafe, in order to get on board Ghaul's ship undetected.
After Nessus, Destiny 2 players went to Io to find Ikora and stop Ghaul's Red Legion from extracting the Traveler's Light from the planet. On Io, though, players also encountered the Taken - a force originally controlled by Oryx in Destiny 2's predecessor, and presumably under the influence and control of another higher power. Thanks to the help of Asher Mir, players manage to learn how to stop the Almighty for good and then head back to the Last City for the final stand against the Cabal and Dominus Ghaul himself.
The Red War campaign was also the perfect setting to explore the Vanguard's mortality, something that Forsaken dealt with in a very different way with Cayde-6 and Uldren Sov. After the Red War had come to a conclusion, the Traveler was heavily injured, and it stayed like that for a long time, up until the day before Beyond Light's launch when a live event took place and the Traveler reformed, healing itself.
Curse of Osiris, Warmind, and Season of Opulence's Crown of Sorrow
Curse of Osiris was the first mini-expansion for Destiny 2, and while it didn't move the story forward a lot, it did bring Osiris back as a character. The exiled legendary Warlock was at the time considered the strongest Guardian alive, and players faced the Vex on Mercury to save him. As for Warmind, it was also rather small in scope and it served the purpose of reintroducing Ana Bray (a side character in Beyond Light) and Rasputin, the Warmind AI.
The Seasons from Year 2 are not particularly memorable in terms of story development, with Black Armory mainly introducing Ada-1 and Season of the Drifter acting as a way to learn more about the character's backstory and relationship with the Nine. An interesting Season was what followed: Season of Opulence. Here, Guardians went aboard Emperor Calus' Leviathan and discovered that one of Calus' Shadows - called Gahlran - was corrupted by the Hive artifact known as Crown of Sorrow, which was later found on the Glykon in Season of the Chosen.
Season of Dawn, Season of the Worthy, and Season of Arrivals
Year 3's storytelling was great, and it set up the events of Year 4 and 5 for Destiny 2 in many ways. Season of Dawn was when Osiris talked the Guardians into using the Sundial, a device that could allow anyone who used it correctly to rewrite time, and the ultimate goal was to bring Saint-14 back into the current timeline by undoing his defeat in the Infinite Forest on Mercury. The Guardians were successful, and the legendary Saint-14 was finally reunited with his lover, Osiris, and lived on to be a pivotal character in Season of the Splicer.
Season of the Worthy saw the return of Ana Bray and Rasputin, who banded together with Zavala in order to make the Warmind strong enough to shoot the Almighty out of its route of collision with the Last City. This is not the biggest story development in the game, considering it's a rather self-contained plot, but it did serve the purpose of building up Rasputin's power for Season of Arrivals.
Season of Arrivals is where things got darker, quite literally. The Darkness arrived in Sol, and the Pyramid Ships appeared everywhere in the system. Rasputin tried to destroy the Black Fleet, unsuccessfully; the Warmind AI was disabled, and humanity prepared for its final stand against the lifelong enemy of the Light. The Darkness tried to commune with Guardians and Eris Morn, but Savathun - the WItch Queen - interfered and made a bargain with Nokris to attain knowledge of the art of necromancy, which she will likely use in the premise of next year's expansion to bring back dead Ghosts.
After Nokris' defeat, Guardians learned that the Darkness wants them to go to Europa, which is where the Beyond Light narrative began. Lastly, before Beyond Light launched, players could go on evacuation missions to help mankind flee the planets of Io, Mars, Mercury, and Titan before the Darkness consumed them. That concludes the list of main plot developments that are no longer in the game, with Destiny 2 players soon having to say goodbye to Forsaken and the Tangled Shore as well.
Destiny 2 is available for PC, PS4, PS5, Stadia, Xbox One, and Xbox Series X/S.