Resubmitting because this issue was not resolved, and my post was moved without any explanation.

Date & Time: Most recently experienced on 7-MAR-21
Frequency: 100% of time time
World name: Irrelevant
Character name: Irrelevant
Retainer name: Irrelevant
NPC name: Irrelevant
Monster name: Cloud of Darkness
Class/Level: Any 80
Party or solo: Party
In-game time: Irrelevant
Area and coordinates: Sphere of Naught, coordinates irrelevant
Housing: Irrelevant
Steps:
1. Enter Eden's Promise: Umbra (Savage)
2. proceed through the fight until the boss uses the ability "Art of Darkness"
3. Note that the version of Art of Darkness where the boss targets all 8 players with line AOEs is significantly louder than the other mechanics in the fight.
*Add more steps if necessary

Connection Specs
- Type of internet connection/provider: Irrelevant, this is an asset issue
- Modem maker/model number: Irrelevant, this is an asset issue

■ PC Specs

To obtain the system information, open the FFXIV launcher and select Config → System Information → Display.

-=-=-=-=- System Information -=-=-=-=-
Irrelevant
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-


Laptop Model Name: Not a Laptop
Laptop Model Number: Not a Laptop

Gamepad Manufacturer: Not using a gamepad
Gamepad Model Name: not using a gamepad
Gamepad Part Number: not using a gamepad

Browser Information
- Name and version of the browser currently in-use: Irrelevant
- Internet Explorer Version: Irrelevant

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■ PS4 Specs

Model Number of the PlayStation®4 You Are Using
- Model Number: Not using a PS4

Model Number of the PlayStation®Vita You Are Using
- Model Number: Not using a PSVita

Information About the Peripherals You Are Using
-Type: Irrelevant
-Maker: Irrelevant
-Model Number: Irrelevant