The one where we... OH, MY TRAVELER, what did you just shoot me with?!

The Craftening & How Bungie Fixes Things

Stale data from other crafting recipes could be applied to new recipes
Bungie uses Live Updates (LUPS) to fix content if needed, but it can't repair the code without a full on update
Bungie implemented some LUPS while working on an actual fix
LUPS have a size limit, can only modify existing content, have limited access to UI changes, and only one LUPS can be active at a time
Bungie chose to start by disabling crafted or enhanced weapons, along with disabling certain perks on crafted/enhanced weapons
This LUPS had issues including weapons that were equipped at the time of deployment kept the behavior, and there was a bug preventing Bungie from un-equipping those items
Bungie then expanded the LUPS to include disabling perks, which initially ran into some size issues, and disabled a wide range of perks to cover all bases
They then booted everyone so the LUPS would fully apply to equipped weapons
Then Bungie prepared a final patch fix that would stop the exploit, determine all existing crafted weapons, determine how invalid weapons would become good weapons, and build validation to confirm it worked

Upgraded system from standard D2 recoil which had more randomness
Went live this season
All weapons have a starting recoil pattern, then as the magazine gets lower, it cycles through a set of recoil patterns
This is reset when you stop firing long enough for the recoil and accuracy to reset
Accuracy cones add a bit of randomness, but these patterns are designed to be learned
Fusion Rifles, Shottys, and Snipers did not get deterministic recoil
Fusions are as impacted by recoil, Shottys have a fixed pattern, and Snipers getting it would make their follow shots way easier
The pattern is predictable, but the accuracy randomness still allows it to be un-exploitable (Bungie has a server-side kill switch though if it was exploited)

Because of weapon crafting bug, both Javelin-4 and Igneous Hammer returning this weekend

The Path of Burning Steps Titan Exotic and associated ornaments no longer change appearance when the Solar Weapon Surge perk is active.
The Hoarfrost-Z and Icefall Mantle Titan Exotics are using the incorrect cooldowns.
When inspecting weapon details for items stored in player vaults, the weapon perk icons may no longer appear.
The Rank 71 Weapon Scrounger Seasonal Bonus displays as requiring ownership of the Season Pass, even if players already own the Season Pass.
Some players who did not fully complete the Season of the Deep story missions may be blocked from completing the current Season of the Witch weekly story mission until they finish the previous Season's story.
Returning players who did not fully complete the A Guardian Rises intro quest prior to the launch of Lightfall are unable to obtain the Learning Light quest.
Multiple pieces of arm armor can cause obstructions when aiming down sights on the Tessellation Exotic Fusion Rifle.