Ark City Guide: Facilities, Nono's Shop & Research Facility in CZN
Ark City is the home hub in Chaos Zero Nightmare, holding six facilities — Research Facility, Policy Office, Epione Center, Garden Cafe, Starshine Diner and Nono's Shop — where you spend Policy Points and unlock combat & story options.
Ark City is the home hub in Chaos Zero Nightmare — the safe base you return to between Chaos runs, holding the shops and facilities that manage your Policy Points, Trauma Codes and combat options.
What's inside Ark City
Ark City is organized into named facilities: Research Facility, Policy Office, Epione Center, Garden Cafe, Starshine Diner and Nono's Shop. Each hosts a different slice of daily and account-progression content.
Research Facility
The Research Facility is where you unlock options for reverting your last action mid-combat. This uses the Protos Skill, which spends Sands of Time — capped at 15 uses per match.
Epione Center & Nono's Shop
The Epione Center substory (Chapter 2, Episode 5) is what unlocks Trauma Code stages once cleared. From there, Nono's Shop — also in Ark City — sells the Special Security Code needed to open a specific combatant's Trauma Code, priced at 20 Policy Points each. See the Trauma Codes guide for the full unlock walkthrough.
Other facilities
Policy Office, Garden Cafe and Starshine Diner round out Ark City's remaining facilities, each covering their own slice of shop and daily-task content inside the hub.
FAQ
| Question | Answer |
|---|---|
| Where do I spend Policy Points? | At Nono's Shop inside Ark City. |
| How many Sands of Time can I use per match? | Up to 15, unlocked via the Research Facility's revert-action options. |
| Do I need to clear anything to open Trauma Codes from Ark City? | Yes — clear the Epione Center substory in Chapter 2, Episode 5 first. |