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Destiny 2: Lightfall | Unfinished Business Exotic quest walkthrough

Here's how to get the Deterministic Chaos heavy machine gun. Just follow these steps.

Unfinished Business is an exotic quest in Destiny 2: Lightfall once the player has completed the main story of the expansion. It’s an important quest to complete as soon as possible, as doing so will grant you the Deterministic Chaos exotic machine gun.

It’s not the most straightforward quest in the world, which is why we’ve written up this Unfinished Business Exotic quest walkthrough.

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Unfinished Business exotic quest

The Unfinished Business exotic quest has 13 steps in total, and can be completed as soon as you finish the main story quest of Destiny 2: Lightfall. It takes roughly 2-3 hours to complete, and requires you to take part in numerous combat encounters.

Unfinished Business | step 1

For step 1 of Unfinished Business, make your way to the Hall of Heroes. You can find this near Nimbus near the Striders’ Gate landing zone.

Screenshot of  Unfinished Business cinematic in Destiny 2: Lightfall
We start with a cool cinematic!

Unfinished Business | step 2

Fast travel to the Striders’ Gate landing zone and speak to Nimbus

Unfinished Business | step 3

For this step, you need to collect cipher qubits from vex in Neomuna, then use them to extract data from Cloud Accretions.

We recommend you fast travel to the Liming Harbor landing zone, as this spot is packed full of Vex that you can kill quickly.

Shooting Vex in Destiny 2: Lightfall
Liming Harbor is the best place for this part of the Unfinished Business quest!

Continue killing Vex in this area (the public event is a great way to collect a lot of qubits) until you’re able to extract five pieces of data. You can track you progress towards this goal by checking Unfinished Business in your Quest tab.

As for finding Cloud Accretions, you can find them scattered around Neomuna. Check out our guide on how to find Cloud Accretions for some tips on completing this step quickly.

As a side note, if you need some Nimbus reputation, pick up some patrols in the harbor and kill two birds with one stone.

Unfinished Business | step 4

For step 4, track the unfinished business quest in your quest tab and follow the waypoint into Maya’s Retreat to the east. You can largely run past all the enemies on the way, as there’s no mandatory kill requirements until you reach the peak.

Maya's Retreat in Destiny 2: Lightfall
Once you see this, you've made it.

Unfinished Business | step 5

Once at the peak of Unfinished Business, you’ll have to survive against several waves of vex. Kill them all, and the quest will be complete! Thankfully, there’s no respawn restriction, so you can take this on without too much concern.

Unfinished Business | step 6

For this step, start by fast travelling to the Liming Harbor landing zone. Make sure the quest is tracked, then follow the waypoint into the Radiosonde to the south. You’ll have to fight through a decent chunk of Vex on the way.

Unfinished Business | step 7

Fast travel to the Liming Harbor landing zone. With the quest tracked, follow the waypoint until you reach a large yellow room. Jump up to the second floor before shooting out a vent on the north wall and jumping into the Lost Sector.

Liming Harbor lost sector in Destiny 2: Lightfall
Here's the entrance to the lost sector!

From here, just progress through the Lost Sector and take out the final boss, then loot the chest at the end to receive the compass quest item.

Unfinished Business | step 8

This is a fun one. Travel to Ahimsa Park and go wild, killing enemies with abilities where possible. A great option for this is to start the Terminal Overload if the public event is located here, as you’ll be thrown against loads of enemies you can chip away at.

Unfinished Business | step 9

Seed of Silver Wings path in Destiny 2: Lightfall
We're back!

This step requires you to travel deep inside the Typhon Imperator, so be sure to track the quest as you have in previous steps.

You’ll eventually reach a large open room, with two shielded spots that you need to access. To open these up, simply clear the room of enemies. Once you have, you should be able to walk up and loot the Seed of Silver Wings.

Seed of Silver Wings room in Destiny 2: Lightfall
Once you reach here, start shooting!

Unfinished Business | step 10

This step is easy enough! Simply head back to Nimbus and talk to him.

Unfinished Business | step 11

For this step, you’ll need to complete the mission “What Remains”. You can access this quest on the path toMaya’s retreat, but track the quest if you need to.

Roughly 60% through this mission, you’ll be given the new exotic heavy Machine gun Deterministic Chaos! For the rest of the mission you’ll be given free heavy ammo, so go ham and use it as much as you want.

Deterministic Chaos on ground in Destiny 2: Lightfall
There it is!

Unfinished Business | step 12

For this step, travel back to Nimbus at Striders’ Gate.

Unfinished Business | step 13

For the final step, simply walk back into the Hall of Heroes and interact with the grave that was erected at the start of the quest chain, and the Unfinished Business exotic quest will be complete!

Final chat in Unfinished Business exotic quest in Destiny 2: Lightfall
We're done! RIP to Rohan.

How to get the Deterministic Chaos catalyst

In order to get the Deterministic Chaos exotic catalyst, you need to keep killing enemies with the weapon until it unlocks automatically. There's no set amount you need to kill, so just keep it equipped and in-use until it pops up.

With that done, you may want to read up on some more Destiny 2: Lightfall guides! Why not read our Strand subclass and fragments piece, as well as our guide on From Zero quest walkthrough.

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