Combat Basics
An in-depth guide on Ark City, Chaos Zero Nightmare’s management/life sim game mode.
Before we get into the details, here are a couple reasons why engaging with Ark City is important for your account progression:
- Increases Aether (stamina) maximum cap. You can increase your Aether cap through the Research Facility.
- More Aether (stamina) per day. The cafe offers 80 Aether or 60 storable Aether once per day.
- Protos Skills. You unlock the ability to undo a card, undo a turn, redraw Ego Skills, and reroll dice through the Research Facility.
- Character Affinity. Building affinity with your characters grants them permanent stat boosts. It’s also required to progress in the Growth Guide, which grants a lot of rewards.
Here’s a quick rundown of Ark City’s daily tasks:
- Approve policies in Policy Center
- Restore 80 Aether at Garden Cafe
- Spend all Communication Passes on excursions in Ark City or therapy in the Epione Center
- Buy all Research Notes from Nono’s Shop
- Spend Research Notes in Research Facility
Excursions and Communication Passes

You get 3 Communication Passes per day (Research Facility can increase this to 4).

You can spend a Communication Pass to go on an excursion with one of your Combatants. You cannot go on more than 1 excursion with the same Combatant in one day. Each day, 2 of your Combatants will randomly spawn in each unlocked area of Ark City. You start with 1 area in each of the four zones—Main Street, Vacation Spot, Academy, and Administrative District. Until you unlock more areas in the Research Facility, if you have more than 8 Combatants, you may not be able to go on an excursion with a specific Combatant if they don’t spawn.
Going on an excursion unlocks a short, visual-novel style scene where you hang out with the Combatant for a while. You unlock a different cutscene every time you go on an excursion with the Combatant to a different area. You can rewatch these scenes any time through the Excursion Collection. Excursions also increase your Affinity with the Combatant, which can unlock stat bonuses and animated character wallpapers for your home page.
You can also spend Communication Passes to give traumatized Combatants counseling in the Epione Center.
Policy Center
At the start of the game and every few in-game weeks, Ark City faces a specific crisis that needs to be resolved within a certain number of in-game days.
1. Pick one of three projects

This will set the stat thresholds you need to reach by the time the crisis happens. There are four stats for Ark City: Happiness, Administrative Index, Economic Activity, and Public Order. You get a different rating (S/A/B/C) depending on how well you meet your project’s stat goals, which determines what rewards you get at the end of the project. Getting C rank always grants 60 Crystals, but whether you get Combatant EXP, Partner EXP, or other materials depends on which project you pick.
2. Assign three Combatants as Aides

Every Combatant specializes in one of the four stats and will regularly propose policies that increase that stat. When you make a decision on a policy, you gain Affinity with the Combatant who proposed it. You can also just click Auto Formation, and the game will assign three of your Combatants for you.
3. Approve policies

Policies are generated every 6 hours until you reach the policy cap. You can speed up policy generation and the policy cap through the Research Facility. Policies require you to make a choice between two options that change Ark City’s stats. Every policy advances the in-game timer by a certain number of days, so make sure you can reach the stat goals before the crisis occurs. Policies also have different Grades: Special, 1st, 2nd, and 3rd.
Approving policies grants Policy Points, with better Graded policies granting more. You can spend these points at Nono’s Shop for Research Notes, gifts, and more policies—as well as a few materials. Remember to approve policies regularly so you can buy out all of Nono’s Research Notes every week until your Research Facility is maxed out.
Starshine Diner

You can purchase food buffs at the Starshine Diner with Units. These buffs apply for your next two Chaos runs, but they do not stack; you can only have one at a time.
Here are some of the options available in the game:
| Food | Effect | Price |
|---|---|---|
| Warm Steamed Meat Bun | +10% Health for all Combatants | 10,000 Units |
| Fluffy Steamed Peach Bun | +5% Health, +5% Passion Attribute Damage for all Combatants | 15,000 Units |
| Sweet and Savory Teriyaki Skewers | +5% Defense, +5% Health for all Combatants | 10,000 Units |
| Juicy Charcoal-Grilled Skewers | +5% Health, +5% Instinct Attribute Damage for all Combatants | 15,000 Units |
| Ocean Breeze Sushi Set | +7% Attack for all Combatants | 8,000 Units |
| Melt-in-Your-Mouth Sushi Set | +5 Attack, +5% Health for all Combatants | 13,000 Units |
| Hearty Hamburger Steak Meal | +5% Defense, +10% Critical Damage for all Combatants | 15,000 Units |
| Cheesy Hamburger Steak | +5% Defense, +10% Critical Damage for all Combatants | 15,000 Units |
Garden Cafe

You can get coffee at the Garden Cafe once per day. There are two options:
- Restore 80 Aether (stamina) immediately
- Get a storable item worth 60 Aether that can stack up to 4 times
Most active players should pick the 80 Aether, but the 60 storable Aether is nice for players who cannot play regularly.
Epione Center

When a traumatized Combatant returns from Chaos, you can treat them in the Epione Center. The Psychotherapy tab presents a list of all currently traumatized Combatants who require care. There are two recovery options you can choose from: Delete Memories and Counseling. Both options prompt a short cutscene showing the Combatant’s recovery.
You can spend Units to delete a character’s memories, which will delete the save file that was generated from their last run. This does not unlock any Counseling Record achievements, but you can do this as many times as you can afford.

You can spend a Communication Pass to provide counseling instead. During counseling, you have to choose between treatment options twice; each option stabilizes the character’s psyche by a certain percentage. You can unlock a 50 Crystal reward when you help a Combatant recover from a specific symptom for the first time; each Combatant has three symptoms they can exhibit. When you have unlocked all three, you get 150 Crystals.

Research Facility

You can purchase up to 35 Research Notes from Nono’s shop per week, and we highly recommend that you do so. This is because you can spend these Research Notes to unlock Learning Nodes, some of which can be very impactful to your CZN experience. We’ve listed all Learning Nodes in the table below, but here’s a week-by-week breakdown highlighting the most important nodes you can unlock.
- Week 1 (0–35 RN)
- Protos Skill Learning - Undo Current Turn: Unlocks the ability to revert the game state to the start of the current turn for 3 hourglasses.
- Advanced Policy Management (unlocks at 1 RN): Increases the maximum number of policies the Policy Center can hold at once, so you don’t have to log in and approve policies every few hours.
- Policy Management Efficiency (unlocks at 1 RN): Decreases policy creation time. More policies = you can buy more Research Notes and other items from Nono’s Shop.
- EXTRA AETHER STORAGE (unlocks at 30 RN): Increases your maximum Aether cap!
- Week 2 (36–75 RN)
- Maximum Communication Passes +1 (unlocks at 40 RN): More Excursions or Counseling per day!
- Supply Chain Circulation Enhancement Policy (unlocks at 45 RN): Increases purchase limits in Nono’s shop! This means you can buy up to 40 Research Notes per week.
- Epiphany Occurrence Theory Study (unlocks at 50 RN): Higher grade policies grant more Policy Points for you to spend in Nono’s Shop. They’re also more effective than normal policies, giving you a better shot at getting a higher grade on your project for more materials.
- Protos Skill Learning - Reroll Dice (unlocks at 55 RN): Unlocks the ability to reroll dice rolls in Chaos for 2 Sands of Time each. Great for improving the consistency of events.
- Protos Skill Learning - EP Skill Redraw (unlocks at 70 RN): Unlocks the ability to redraw the Ego Skill pile, potentially reordering them.
- Week 3 (76–115 RN)
- Aether Extraction Efficiency Research (unlocks at 75 RN): Increases your maximum Aether cap even further!
- Sands of Time Accumulation Device (unlocks at 90 RN): Increases the number of Sands of Time you get per day.
All Learning Nodes
| Learning Node | Effect | Available to unlock after spending a total of… |
|---|---|---|
| Protos Skill Learning | Unlock Undo Current Turn Protos skill (This allows you to spend 3 hourglasses to revert the game state to the start of the current turn.) | 0 RN |
| Advanced Policy Management | Increase maximum number of policies to 4/5/6/7/8 | 0 RN |
| Blackhorn Trade Expansion Contract | Gain an additional 1/2/3/4/5 Affinity when implementing a policy proposed by a combatant | 5 RN |
| Reinforcing Trauma Treatment Facilities | Gain an additional 1/2/3/4/5 Affinity upon successfully treating a traumatized combatant | 10 RN |
| Tourist Density Expansion Program | Unlock Vacation Spot - Paradise Resort areas for Excursion | 10 RN |
| Bond Strengthening Training | Gain an additional 2/4 Affinity upon going on an excursion with Agents | 15 RN |
| Policy Management Efficiency | Decrease new policy creation time to 348/336/324/312/300 minutes | 15 RN |
| Administrative Network Reinforcement | Unlock Administrative District - STA areas for Excursion | 15 RN |
| Mind Reading Techniques | Gain an additional 1/2/3/4/5 Affinity upon giving a gift | 20 RN |
| Main Street Revitalization Policy | Unlock Main Street - Financial Plaza areas for Excursion | 20 RN |
| Public Administration Resilience Plan | Decrease Tourism Index loss from calamity by Happiness | 25 RN |
| Academy District Revitalization | Unlock Academy - Chaos Lab areas for Excursion | 25 RN |
| Extra Aether Storage | Increase the amount of Aether that can be stored by 5/10/15/20/25 | 30 RN |
| Order Restoration Algorithm | Decrease Tourism Index loss from calamity by Administrative Index | 30 RN |
| Crisis Financial Response | Decrease Tourism Index loss from calamity by Public Order Index | 35 RN |
| Unofficial Excursion Permit | Maximum Communication Passes +1 | 40 RN |
| Tourism Crisis Management Model | Decrease Tourism Index loss from calamity by Economic Activity | 40 RN |
| Supply Chain Circulation Enhancement Policy | Increase the number of purchase limit at Nono’s Shop by 1/2/3/4/5 | 45 RN |
| Ark Tourism Promotion Plan | Unlock Vacation Spot - Adventure Starport areas for Excursion | 45 RN |
| Epiphany Occurrence Theory Study | Increase Special Grade policy occurrence chance by 10% | 50 RN |
| Infrastructure Enhancement Policy | Unlock Administrative District - Ark Service Network areas for Excursion | 50 RN |
| Protos Skill Learning | Unlock Reroll Dice Protos skill (allows you to spend 2 Sands of Time to reroll a die in Chaos runs) | 55 RN |
| Resonating Heart | Gain an additional 1/2/3/4/5 Affinity when implement a policy proposed by a combatant | 55 RN |
| Urban Regeneration Policy | Unlock Main Street - Mega Stadium areas for Excursion | 55 RN |
| Companion Treatment Enhancement Model | Gain an additional 1/2/3/4/5 Affinity upon successful treatment of a traumatized combatant | 60 RN |
| Educational Hub Development Plan | Unlock Academy - Level Up Hub areas for Excursion | 60 RN |
| Unexpected Fortune | 5/10/15/20/25% chance of receiving extra rewards when going on an Excursion | 65 RN |
| Protos Skill Learning | Unlock EP skill redraw Protos skill (allows you to spend 2 Sands of Time to redraw the Ego Skill pile, potentially reordering them) | 70 RN |
| Administrative Recovery Resilience Model | When a disaster occurs, the decrease in Happiness is reduced by 1/2/3/4/5 | 70 RN |
| Concentrated Tourist Area Development Plan | Unlock Vacation Spot - Omatsuri Town areas for Excursion | 70 RN |
| Aether Extraction Efficiency Research | Increase the amount of Aether that can be stored by 5/10/15/20/25 | 75 RN |
| Social Stabilization Model | When a disaster occurs, the decrease in Administrative Index is reduced by 1/2/3/4/5 | 75 RN |
| Administrative District Advancement | Unlock Administrative District - Mecha Tower areas for Excursion | 75 RN |
| Bond Enhancement Process | Gain an additional 2/4/6 Affinity when on an excursion with Agents | 80 RN |
| Financial Stabilization Model | When a disaster occurs, the decrease in Public Order Index is reduced by 1/2/3/4/5 | 80 RN |
| Major Building Expansion Plan | Unlock Main Street - Heritage Museum areas for Excursion | 80 RN |
| Mental Empathy Training | Gain an additional 1/2/3/4/5 Affinity upon giving a gift | 85 RN |
| Tourism Recovery Management Model | When a disaster occurs, the decrease in Economic Activity is reduced by 1 | 85 RN |
| Educational District Revitalization Plan | Unlock Academy - Academy House areas for Excursion | 85 RN |
| Sands of Time Accumulation Device | Receive 1/2/3/4/5 additional Sands, that recharges daily | 90 RN |
| Practical Urban Management Training | Increases the number of Agents who appear for Excursions to 20 | 90 RN |
Nono’s Shop

Nono’s shop provides a variety of items that you can purchase with the Policy Points you earn from approving policies. Here’s a list of what she offers, in order of importance:
- Multidimensional Alignment Material: Allows you to select a Main Stat when crafting a Memory Fragment.
- Special Security Code: Unlocks an agent’s Trauma Code.
- Research Notes: The only way to progress your Research Facility. It’s very important to buy all of them every week until your Research Facility is maxed out.
- Policies: Extra policies that you can propose at any time.
- Gifts: You can give Gifts to Combatants to raise their Affinity.
- Units: Buying these at Nono’s Shop isn’t particularly efficient.





