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Zenless Zone Zero (ZZZ)
Old Observatory Area 2 Guide
☆ New: Tier List Maker & Community Tier List Contest!
★ Upcoming: Version 2.5, Zhao, & Ye Shunguang!
☆ 2.4 Agents: Dialyn, & Banyue
★ 2.3 Phase 2: Yidhari Release & Ju Fufu Rerun
☆ Tier Lists: Agents | W-Engines | Bangboos | Teams
★ Redeem Codes for free Polychromes!
Old Observatory is The Mystery of Arpeggio Fault's Stage 2 Area in Zenless Zone Zero (ZZZ). See the Area 2 guide for each floor, the quest walkthrough, and the rewards here!
| The Mystery of Arpeggio Fault Event | |||||
|---|---|---|---|---|---|
 Fault Surface |
 Old Observatory |
 Outpost Beacon |
|||
 Laboratory Ruins |
 Turbulent Corridor |
 Bangboo Password |
|||
| Slumbering Land Quest | Where the Mystery Went Quest | ||||
List of Contents
Old Observatory Stage Details
The Mystery of Arpeggio Fault Stage 2 Details and Floors
| Mechanic | Enemy ATK +50%, generate a large number of bombs every floor. |
|---|---|
| Floors |
16F - Prep Area 19F - Shallows 23F - Mid-Level 26F - Depths 30F - Fault Floor |
Recommended Data File
| Data File | Data File Details |
|---|---|
 Demolition Squad |
Initial Effects Receive bomb-related Sub Strategies when levelling up. |
|
Full Effects • Explosive Stamina Immediately obtain 8 bombs • Explosion Expert Bombs deal +10 DMG to enemies, explosion length +2 • High Explosives Protagonist gains +50 HP. • Detonate and Dominate Bombs will explode immediately. Protagonist ATK +1 when detonating a bomb • Blast Suit Take no DMG from detonations, instead recovering 5 HP |
Old Observatory Area 2 Guide
Arpeggio Fault Area 2 Strategy
- Collect Contribution Points at the Start
- Get All the Cross Blast Bombs
- Get Silk From Merchants
- Take Advantage of Rest Areas
- Carefully Choose Buffs
Collect Contribution Points
In the first few floors, collect as many Contributions Points to either upgrade to two Agent helpers or to get higher tier Agents who can support you within Area 2.
You can upgrade to get two agents by giving the Pink Gun TV Tile 50 Contribution Points.
Get All the Bombs
Get as many Cross Blast plug-ins as possible and use them sparingly on walls or tactical spikes blocking items.
Get Crimson Silk From Merchants
Merchants in the Arpeggio Fault are different from the usual Merchants in Hollow Zero. You can set bombs on them and once they disappear, in their place are numerous Crimson Silks.
Take Advantage of Rest Areas
If you have a lot of bombs, especially the Resonia, which adds two more bombs when you release one, interact with the RIP Rest Areas until they disappear.
It will spawn strong enemies but it will also release numerous rewards.
Choose Your Plug-Ins and Resonia
In this stage, it's important to choose Plug-Ins or Resonia which will increase your HP and buff your bombs. HP specifically for you and your Agents so you can withstand damage.
The Mystery of the Arpeggio Fault Unravelling Quest Guide
Head to the Old Observatory Area
Teleport back to the Scott Outpost Interior and complete all the Old Observatory Area 2 Stages.
Talk to Soldier 11
After completing all the Area 2 Stages, talk to Soldier 11 outside of the tent. Then, talk to the No.4412 Bangboo about your findings on their Master, Alowyn Mystik.
All Old Observatory Rewards
Old Observatory Hollow Zero Rewards
| Stage | Rewards |
|---|---|
| Prep Area |
 Polychrome
x30 Denny
x10,000 |
| Shallows |
Polychrome
x30 Denny
x10,000 |
| Mid-Level |
Polychrome
x30 Denny
x10,000 |
| Depths |
Polychrome
x30 Denny
x10,000 |
| Fault Floor |
Polychrome
x30 Denny
x10,000 |
Stage 2 Event Exclusive Rewards
| Stage | Rewards |
|---|---|
| Complete all stages in OId Observatory |
Polychrome
x50 Denny
x10,000 |
| Upgrade you squad 20 times during exploration |
Polychrome
x30 Denny
x10,000 |
| Pick up Crimson Silk a total of 20 times while exploring |
Polychrome
x30 Denny
x10,000 |
Old Observatory Information
Part of The Mystery of Arpeggio Fault Event
Old Observatory is Stage 2 of The Mystery of Arpeggio Fault Hollow Zero Event! During this stage, you must get as much bombs as possible to go through the obstacles.
The Mystery of Arpeggio Fault Event Guide
Zenless Zone Zero Related Guides
The Mystery of Arpeggio Fault Event Guide
Arpeggio Fault Quests and Stages
| Areas | Related Quests |
|---|---|
| Fault Surface |
The Mystery of Arpeggio Fault: Special Investigation |
| Old Observatory |
The Mystery of Arpeggio Fault: Unravelling |
| Outpost Beacon |
The Mystery of Arpeggio Fault: Final Puzzle Piece |
| Laboratory Ruins (Floor 52-64) |
The Mystery of Arpeggio Fault: Corruption Crisis |
| Turbulent Corridor (Floor 67-81) |
|
| Laboratory Ruins (94F-B & 99F-B) |
Arpeggio Fault Follow-Up Investigation - Where the Mystery Went |
| Turbulent Corridor (87F-B & 88F-B) |
Arpeggio Fault Follow-Up Investigation - Slumbering Land |
Other Arpeggio Fault Guide
| Other Event Guides |
|---|
| Password Locations and Arpeggio Fault Secret |
Other Current and Upcoming Events
Comment
Author
Old Observatory Area 2 Guide
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