Deep Sleep Quest and Battle Guide
☆ New: Tier List Maker & Community Tier List Contest!
★ 2.5: Livestream, Version, Zhao, & Ye Shunguang!
☆ 2.4 Phase 1 Agents: Dialyn & Hugo
★ 2.4 Phase 2 Agents: Banyue & Ellen
☆ Tier Lists: Agents | W-Engines | Bangboos | Teams
★ Redeem Codes for free Polychromes!
Deep Sleep is part of the When Dreams Remain Unfinished event in Zenless Zone Zero (ZZZ) 2.3. See all Deep Sleep combat and quest guides, recommended companions, and all the rewards here!
| When Dreams Remain Unfinished Guides | ||
|---|---|---|
 Event Guide |
 Light Nap Day 1 Guide |
 Deep Sleep Day 2 Guide |
 Dream Abyss Day 3 Guide |
 Simulation Challenge |
 Companion Database |
Dream Investigation - Deep Sleep Guide
All Deep Sleep Event Stages
| Dream Investigation - Deep Sleep | ||
|---|---|---|
| 1 | Dream of Port Elpis Story | Deep Sleep Battle (I) Combat |
| 2 | Birthday Present Story | Deep Sleep Battle (II) Combat |
| 3 | Clues on Darkwater Research Center Story | Deep Sleep Battle (III) Combat |
| 4 | Tales from the Docks Story | Deep Sleep Battle (IV) Combat |
| 5 | Deep Sleep Battle: Troublemaker Combat | Phantoms of the Past Story |
Click on the links to jump to a guide!
Deep Sleep Combat Guides
Deep Sleep Battle I Guide
| Dream Description | Command your Mechanical allies to eliminate enemies. Use type advantages to inflict extra DMG against biological foes. And don't forget Energy is vital for Mechanical allies, so make the most of the Beholder Engine to recharge them! |
|---|---|
| Recommended |  Machine |
| Companion |
 Light Patroller |
Beholder EngineRecharge Energy
In the first battle stage, you will be utilizing Machine companions, and managing energy consumption is crucial for playing effectively with this squad.
Use the Beholder Engine's skill shot, Energy Recovery, to restore an ally's energy while also dealing damage to enemies along the path of the shot.
Deep Sleep Battle II Guide
| Dream Description | The enemy Flame Dreamer will keep granting buffs to his allies - make sure to take him out first! |
|---|---|
| Recommended | Machine |
| Companion |
 Medium Patroller Light Patroller |
Eliminate the Flame Dreamer
In the second battle stage, defeating the Flame Dreamer is crucial as it enhances the attacks of its allies. Focus all of your units' skills on this enemy.
Deep Sleep Battle III Guide
| Dream Description | The enemy Dreaming Hymnist will empower the Bulky Enforcers. Use the Heavy Striker Mark IIs area DMG skill to deal with them and reduce the threat posed by Bulky Enforcers. |
|---|---|
| Recommended | Machine |
| Companion |
Medium Patroller Light Patroller |
Heavy Striker MK IICast an AoE Skill on Enemies
In the third battle stage, the Dreaming Hymnist will enhance the Bulky Enforcers' attacks! It's time to use Heavy Striker MK II's AoE skill to damage multiple enemies at once.
Deep Sleep Battle IV Guide
| Dream Description | The enemy Flame Dreamer will keep buffing the Bulky Enforcer. Try using Terror Raptor's single-target burst skill to take down the Flame Dreamer first. |
|---|---|
| Recommended | Machine |
| Companion |
Medium Patroller |
Terror RaptorCast Terror Raptor's Burst Skill
In the fourth battle stage, you'll face two Bulky Enforcers alongside a Flame Dreamer. To complete this stage successfully, target the Flame Dreamer first.
After defeating it, activate Terror Raptor's Burst skill to launch missiles and deal significant burst damage.
Deep Sleep Battle - Troublemaker Guide
| Dream Description | This is the strongest enemy in this dream zone. Try making use of Auxiliary Plug-In effects and finish it off with Terror Raptor's single-target burst skill! |
|---|---|
| Recommended | Machine |
| Companion |
Medium Patroller |
Stack Energy and Use Terror Raptor's Burst
You are now up against Rampant Brute and its biological allies. First, utilize the Medium Patroller and the Beholder Engine's skill, Energy Recovery, to accumulate energy for the Terror Raptor.
Next, use Heavy Striker MK II's AoE skill on the Dreaming Hymnist. Once it’s the Terror Raptor's turn, activate its Burst skill to deal massive Burst damage to the clustered enemies.
Deep Sleep Story Quest Guides
Dream of Port Elpis Quest Guide
| Quest Walkthrough | |
|---|---|
| 1 |  For the second time, head inside Yidhari's dream and explore around Port Elpis this time. Speak to Manato and Lucia to deal with the Port Boy. |
Birthday Present Quest Guide
| Quest Walkthrough | |
|---|---|
| 1 |  After the battle, meet up with Yidhari and Grandpa Gu as they seem to know each other. |
| 2 |  Head down to the docks and speak with everyone to discuss the plans. |
| 3 |  Follow the quest marker leading to the fish statue and interact with the Shipping Records. |
Clues on Darkwater Research Center Quest Guide
| Quest Walkthrough | |
|---|---|
| 1 |  Interrogate the dock security guard and ask him about the Darkwater Research Center. |
| 2 |  Speak with Captain Morgan to hear more details from him, but he seems not to be cooperating; this will lead to another battle. |
Tales from the Docks Quest Guide
| Quest Walkthrough | |
|---|---|
| 1 |  After defeating the captain, explain the situation to him and ask for his cooperation. |
| 2 |  To gain the captain's trust, approach the enemies and defeat them in battle. |
Phantoms of the Past Quest Guide
| Quest Walkthrough | |
|---|---|
| 1 |  Help out Yidhari in convincing Captain Morgan to share the details he knows about the Darkwater Research Center. |
| 2 |  Watch the dialogue cutscene as they reveal the truth about Yidhari's parents. |
| 3 |  After learning the truth, talk to Yidhari about the next plans, but she wants to resolve it on her own. |
Deep Sleep Exclusive Rewards
Dream Investigation Day 2 Rewards
| Objective | Rewards |
|---|---|
| Complete Deep Sleep Battle (I) |
 Polychrome
x30  Denny
x10,000 |
| Complete Deep Sleep Battle (II) |
Polychrome
x30 Denny
x10,000 |
| Complete Deep Sleep Battle (III) |
Polychrome
x50 Denny
x10,000 |
| Complete Deep Sleep Battle (IV) |
Polychrome
x50 Denny
x10,000 |
| Complete Deep Sleep Battle: Troublemaker |
Polychrome
x50 Denny
x10,000 |
| Complete all Deep Sleep investigation stage commissions |
Polychrome
x60 Denny
x10,000 |
Senior Investigator Log
W-Engine Energy Module
Specialized Ether ChipDeep Sleep Information
Part of the When Dreams Remain Unfinished Event
Deep Sleep is part of the Dream Investigation story and battle mode within the When Dreams Remain Unfinished event.
During the event, Proxies must deploy Mechanical companions to battle against the enemies and complete the story commissions.
When Dreams Remain Unfinished Guide
Zenless Zone Zero Related Guides
When Dreams Remain Unfinished Event
Dreams Remain Unfinished Guides
| When Dreams Remain Unfinished Guides | |
|---|---|
| Simulation Challenge |
Companion Database |
All Dream Investigation Quests
| Unlock | Day | Quest & Stage Guides |
|---|---|---|
| Oct. 17, 2025 | |
Light Nap Quest and Battle Guide |
| Oct. 19, 2025 | |
Deep Sleep Quest and Battle Guide |
| Oct. 21, 2025 | |
Dream Abyss Quest and Battle Guide |
Other Current and Upcoming Events
Comment
Author
Deep Sleep Quest and Battle Guide
Rankings
Gaming News
Popular Games
Genshin Impact Walkthrough & Guides Wiki
Umamusume: Pretty Derby Walkthrough & Guides Wiki
Where Winds Meet Walkthrough & Guides Wiki
Pokemon Legends: Z-A Walkthrough & Guides Wiki
Honkai: Star Rail Walkthrough & Guides Wiki
Wuthering Waves Walkthrough & Guides Wiki
Digimon Story: Time Stranger Walkthrough & Guides Wiki
Clair Obscur: Expedition 33 Walkthrough & Guides Wiki
Pokemon TCG Pocket (PTCGP) Strategies & Guides Wiki
Zenless Zone Zero Walkthrough & Guides Wiki
Recommended Games
Diablo 4: Vessel of Hatred Walkthrough & Guides Wiki
Fire Emblem Heroes (FEH) Walkthrough & Guides Wiki
Yu-Gi-Oh! Master Duel Walkthrough & Guides Wiki
Elden Ring Shadow of the Erdtree Walkthrough & Guides Wiki
Super Smash Bros. Ultimate Walkthrough & Guides Wiki
Monster Hunter World Walkthrough & Guides Wiki
Pokemon Brilliant Diamond and Shining Pearl (BDSP) Walkthrough & Guides Wiki
The Legend of Zelda: Tears of the Kingdom Walkthrough & Guides Wiki
Persona 3 Reload Walkthrough & Guides Wiki
Cyberpunk 2077: Ultimate Edition Walkthrough & Guides Wiki
All rights reserved
Copyright © 2024 HoYoverse, COGNOSPHERE. All Rights Reserved.
The copyrights of videos of games used in our content and other intellectual property rights belong to the provider of the game.
The contents we provide on this site were created personally by members of the Game8 editorial department.
We refuse the right to reuse or repost content taken without our permission such as data or images to other sites.