Deterministic Chaos is an exotic Heavy Machine Gun that weakens enemies on every fourth shot and makes them Volatile every sixteenth shot. To get it, you will need to complete an Exotic Quest called Unfinished Business which can only be accessed after completing the Lightfall campaign. It is a 360 RPM Void Machine Gun which is fairly decent for clearing adds. This guide will help you learn everything you need to know about completing Unfinished Business to acquire Deterministic Chaos.
Destiny 2: Lightfall Unfinished Business Exotic Quest
There are multiple steps involved in completing the Unfinished Business. a majority of these steps take place in Neomuna but the last step will take you to a familiar location on the Moon.
Hall of Heroes
After completing the story, visit the Hall of Heroes for a small cutscene. After it is complete, speak with Nimbus at his usual spot.
Collecting Materials
For the next step, you will need to collect Cipher Qubits by defeating Vex — you will find plenty in the Liming Harbor. You need around 40x Cipher Qubits. Once done, you will need to find some Cloud Accretions which are the Planetary Materials on Neomuna. After you are done, you will need to visit Maya’s Retreat.
Maya’s Retreat
You will find this area in the bottom right corner of the map. This is the same place where you practised Strand during the campaign. After heading there, you will need to interact with the Vex Conflux, defeat some Vex that appear, and recover the Data Packet. After defeating enemies, interact with the Vex Conflux again.
Meeting with Nimbus
After collecting the Data Packet, meet with Nimbus and Osiris in Radisonde which should be close to your position.
Vex Compass from Thrilladome
For this step, you will need to head over to the Liming Harbor and enter the Lost Sector named Thrilladome — you will need to break a small vent to enter it. Complete the Lost Sector and open the Treasure Chest at the end.
Defeat Cabal in Ahimsa Park
This one is fairly simple. You will need to defeat 100 Shadow Legion (Cabal) in Ahimsa Park. If you defeat with Abilities, you will receive bonus progress but defeating 100 should not be an issue.
Collect a Seed of Silver Wings
To acquire a Seed of Silver Wings, you will need to infiltrate Typhon Imperator, Calus’ ship. Once you are in, keep on progressing forward until you arrive in an open area — the very same place where Caiatl saves us during campaign. After defeating all the enemies, collect the item to move onto the next step.
Acquire Rohan’s Passkey
After collecting a Seed of Silver Wings, return to Nimbus to receive Rohan’s Passkey. It is important to note that this item goes into your Power Weapon slot and not inventory. Therefore, make sure you have some space.
Complete What Remains Mission
For the last step, you will need to complete a mission named What Remains. It is a fairly straightforward mission that will take you to a familiar location … but in reverse. I do not want to spoil it here but it should not be hard. At the end of this mission, you will receive the Deterministic Chaos.
This is how to complete Unfinished Business in Destiny 2: Lightfall for Deterministic Chaos, the exotic Machine Gun. If you have any other questions, be sure to let us know!