Zenless Zone Zero Old Capital Metro Guide - Theria Games

Introduction to Zenless Zone Zero Old Capital Metro Guide

Old Capital Metro is the second unlockable zone within Hollow Zero in Zenless Zone Zero, offering a deeper dive into the game’s layered rogue-lite mechanics. This stage builds upon the fundamentals introduced in the initial zone, increasing the overall difficulty while introducing new strategic challenges centered around the Corruption system.

A core mechanic in Old Capital Metro is the management of Corruption, which becomes a significant threat as players progress. As Pressure accumulates through battles and node interactions, reaching the maximum threshold of 100 triggers the Corruptions penalty—a debilitating effect that can drastically reduce a squad’s survivability and combat effectiveness. Players must carefully monitor their Pressure levels and plan routes that mitigate this buildup, balancing risk versus reward as they traverse the map.

Additionally, this stage introduces the “Overload Distribution” Resonia Collection. This specific set synergizes with the Corruption mechanic by granting bonus damage whenever Pressure Overload occurs. For advanced players, this opens up a high-risk, high-reward playstyle where deliberate Corruption gain can be leveraged to deal significant burst damage, turning a potential penalty into a tactical advantage.

Mastering Old Capital Metro requires a keen understanding of route planning, efficient combat strategies, and calculated use of Resonia effects to maximize rewards while keeping Corruption in check.

How to Unlock Old Capital Metro

Unlocking Old Capital Metro in Zenless Zone Zero requires players to meet several progression milestones across story, level, and reputation systems. As the second stage in Hollow Zero, it’s gated behind both player level and specific quest completions to ensure readiness for its increased difficulty.

To begin, players must first complete the “Qualification Assessment/Outer” as part of the Main Story. This serves as the initial access point to the Hollow Zero system. Hollow Zero itself becomes available upon finishing Chapter 1 of the Main Story. Once Hollow Zero is unlocked, progressing further to Old Capital Metro requires a multi-step process.

The first step is to complete the sub-quest “Art of War: Simple Edition,” which becomes available at Inter-Knot Level 18. Following this, players need to advance their Reputation to the “Certified Proxy” rank, which is achieved by passing a Reputation Promotion Exam. This exam becomes accessible upon reaching Inter-Knot Level 21, triggering the sub-quest “Unexplored Station”.

After acquiring the “Certified Proxy” title and reaching Inter-Knot Level 21, players can then access the Hollow Zero Qualification Assessment: Edge. Successfully clearing this assessment unlocks the Old Capital Metro stage.

In addition to unlocking the base version of Old Capital Metro, higher difficulty tiers—Frontline, Interior, Heartland, and Core—become available as players continue to level up. These unlock at Inter-Knot Levels 25, 30, 35, and 40, respectively, and require progression through additional Main Story commissions. Completing Old Capital Metro: Frontline is also a prerequisite for accessing subsequent zones, making it a key milestone in Hollow Zero advancement.

Old Capital Metro Stages and Details

Old Capital Metro consists of five progressively challenging stages within Zenless Zone Zero’s Hollow Zero, each escalating in difficulty, floor count, and strategic complexity. This zone heavily emphasizes Corruption management, encouraging players to balance power boosts and risks through intentional Pressure buildup. Strategic planning, team synergy, and efficient route selection are key to surviving and succeeding in its deepening layers.

The first stage, Old Capital Metro: Edge, unlocks once players reach Inter-Knot Level 21 and complete the Qualification Assessment: Edge. However, the stage is recommended for players at Level 25 or higher due to the tougher enemy compositions and Pressure mechanics. Edge contains 2 floors and introduces Trial No. Five, which features enemy units with resistances that require Ice and Ether attributes to overcome effectively. Preparing a squad that includes these elements helps maintain DPS consistency and clears enemies quickly while managing Pressure buildup efficiently.

Old Capital Metro: Frontline becomes available at Level 30, maintaining a 2-floor layout, but offering a clear spike in difficulty over Edge. Pressure increases more rapidly here, and enemy mechanics become more aggressive. This stage serves as a transitional challenge between early and mid-Hollow Zero runs, reinforcing the importance of properly utilizing Event nodes to control Corruption. By this stage, using Resonia effects that scale with Corruption or provide Pressure relief becomes vital, and players are expected to fine-tune their combat and resource management to progress consistently.

At Level 35, players gain access to Old Capital Metro: Interior, which expands the challenge to 3 floors. This increase in length demands more resource conservation across runs, from healing and Corruption control to Decibel management for Resonia skills. Enemies begin to appear with more layered buffs and debuffs, requiring more deliberate planning in both squad composition and route selection. Overload Distribution Resonia effects, which amplify team-wide damage and restore HP during Pressure Overloads, become increasingly important here, supporting an aggressive but risky playstyle.

Old Capital Metro: Heartland, available at Level 40, maintains the 3-floor format and continues to intensify both enemy behavior and map difficulty. Corruption effects apply more frequently and with greater severity, often stacking if not managed through Event spaces like the Purification Room or the Corruption Door. Enemies may appear in waves, and elite units can drastically alter the flow of combat. At this stage, teams with reliable stun, shielding, and healing support become essential, and tactical use of Perfect Assists and Assist Follow-Ups can determine success in tight battles.

Finally, Old Capital Metro: Core unlocks at Level 45, marking the most challenging version of the zone. Like Heartland, it features 3 demanding floors filled with elite enemies, Corruption hazards, and dense encounter patterns. Players will need fully optimized squads, upgraded Resonia Collections, and a precise understanding of their Pressure economy to make it through. Core emphasizes sustained performance under pressure—literally—where efficient route planning, event prioritization, and offensive momentum through Corruption-enhanced Resonia bonuses can be the deciding factors in victory.

Throughout all stages of Old Capital Metro, one of the key defining features is the Corruption system, which activates as Pressure builds up during a run. Once Pressure hits 100, a Corruption debuff is applied, affecting your squad until it is removed through certain events or mechanics. These effects range from reducing healing efficiency to weakening damage or skill performance. Players can encounter event spaces such as the Purification Room, which clears Corruption, or Corruption Doors, which offer randomized effects that can either cleanse debuffs or grant tactical advantages in exchange for greater risk.

Before starting a run, players may receive a Researcher Offer—an optional buff that applies Corruption at the start of the run in exchange for bonuses. Accepting it provides a damage boost when under Corruption and gives 2 to 3 A-Rank Resonia Collection pieces, giving players a strong early advantage. This choice supports a high-risk, high-reward approach, especially when paired with styles like Overload Distribution, which increases all squad members’ damage by 5% per Pressure Overload stack (up to 50%) and restores 5% HP per stack.

Among the many Corruption debuffs, several are especially disruptive and should be prioritized for removal. These include Frightened, which drastically reduces survivability; Demotivation, which lowers morale and effectiveness; Sinister Resonance, Weakness, Energizing Effect, and Resonia Collection Rejection, each of which negatively impacts damage output, Resonia synergy, or overall performance. Identifying and cleansing these early can be critical to maintaining momentum during longer, multi-floor runs.

In summary, each stage in Old Capital Metro not only tests your team’s raw strength but also your ability to make smart, adaptive decisions under pressure. By leveraging attribute advantages, efficient Resonia loadouts, and tactical route planning, players can turn Corruption into a strategic tool rather than a mere penalty—paving the way toward deeper Hollow Zero mastery.

Recommended Team Builds and Resonia Collections

To effectively tackle Old Capital Metro in Zenless Zone Zero, building a well-synergized team and selecting the appropriate Resonia Collections is crucial—especially given the stage’s emphasis on Corruption and attribute-targeted combat. The boss enemies within this zone are particularly vulnerable to Ice and Ether attributes, making teams centered around Ice characters especially effective.

For optimal performance, it’s recommended to structure your squad around Ice Attribute characters. Strong options include Ellen and Zhu Yuan as primary Attack agents, delivering high burst damage and consistent Ice-based effects. For disruption and crowd control, Lycaon serves as an excellent Stun agent, offering both synergy with Ice teams and Corruption management potential. In the Support role, characters like Nicole and Soukaku can provide crucial assists, healing, shielding, and pressure control—all essential for navigating longer stages with rising Corruption levels.

If an Ice-based Attack agent isn’t available, players should instead utilize their strongest Attack-focused character, regardless of attribute, and build the team and Resonia Collection around that character’s strengths. The key is maintaining a high-damage output while managing Corruption effects efficiently.

In terms of Resonia Collection effects, several styles stand out depending on team composition:

Freeze Style is ideal for Ice-centric squads. This style boosts Ice Damage and enhances Freeze-related effects, amplifying both offensive capabilities and crowd control. Resonia sets like Cutie Cold Pack are especially effective in this style.

Energy Style boosts Energy Decibel acquisition and increases Skill Damage, supporting frequent skill usage and maximizing the effectiveness of characters that rely heavily on active abilities.

Critical Hit Style enhances overall damage potential through increased CRIT Rate and CRIT DMG, making it a strong universal option for burst-heavy builds.

Support Style enhances Perfect Assists and Assist Follow-Ups, while also offering Energy recovery and Shield generation, improving both survivability and team synergy—particularly in longer runs or multi-floor stages.

Additionally, the Overload Distribution Resonia Effect plays a key role in runs within Old Capital Metro. This passive boosts all squad members’ Damage by 5% per Pressure Overload, stacking up to 50%, while also restoring 5% of each member’s Max HP per stack. While this effect can be risky due to the Corruption trade-off, it enables aggressive playstyles that can quickly dispatch elite enemies and bosses if managed correctly.

Combining strong attribute-based team builds with Resonia styles tailored to your leader’s role allows players to fully capitalize on the stage’s mechanics and rewards while staying resilient under the pressure of Corruption buildup.

Rewards from Old Capital Metro

Clearing stages in Old Capital Metro within Zenless Zone Zero’s Hollow Zero provides a wide variety of rewards, ranging from essential materials for character and Bangboo enhancement to valuable currencies used across the game. These rewards scale based on stage difficulty and progression, and many are structured to encourage continued participation in Hollow Zero content.

Upon clearing a stage for the first time, players are granted one-time First Clear Rewards. For example, completing Old Capital Metro: Edge yields:

Inter-Knot Credit x600, used for progression and unlocking features.

Polychrome x80, the premium currency used for character pulls and shop purchases.

Boopon x1, a summon ticket used for pulling Bangboo units.

Withered Crystal: Heaven’s Azure x400, a core resource for upgrading Resonia and other key materials.

Investigation Point x1000, which contributes to License Level progression and Hollow Zero ranking.

Subsequent clears of higher difficulty stages like Old Capital Metro: Frontline offer regular stage rewards designed to support daily and weekly upgrade needs. These typically include:

Investigation Point x1000, contributing to long-term Hollow Zero progression.

Withered Crystal: Heaven’s Azure x400, ensuring a steady supply of this crucial upgrade material.

Bangboo Algorithm Module x7–8, used for upgrading Bangboo stats and abilities.

Bangboo System Widget x2–3, rarer materials also used in Bangboo development.

Denny x675, the core in-game currency used for purchases and upgrades.

Outside of direct stage clears, Hollow Zero offers additional reward systems tied to Old Capital Metro:

Bounty Commissions are weekly resetting missions exclusive to Hollow Zero. Completing them provides valuable items such as Bangboo Enhancement Materials, Polychromes, and Boopons, making them a consistent source of rewards for active players.

License Level progression, earned through accumulating Investigation Points, grants one-time milestone rewards. These often include Polychromes, Boopons, and other enhancement materials, encouraging players to complete stages and reach higher License Tiers.

Players can also interact with Ray at Scott Outpost, who offers Research Progress rewards once Old Capital Metro has been unlocked. These are one-time bonuses awarded based on the player’s advancement through Hollow Zero stages and research completion.

Lastly, Casper at Outpost Logistics operates a Z-Merit Exchange Shop, where players can spend Z-Merits—a currency earned by progressing through Hollow Zero stages and challenges. The shop offers a variety of useful items including materials and upgrade resources, with the inventory refreshing monthly, giving players ongoing incentive to explore and clear Hollow Zero content.

Altogether, the reward structure in Old Capital Metro supports both immediate progression and long-term development, making it a vital component of a player’s overall resource economy in Zenless Zone Zero.

Tips and Strategies for Old Capital Metro and Lost Items

Efficient progression in Hollow Zero begins with unlocking and focusing on Old Capital Metro, as it acts as a key stepping stone into the deeper mechanics and rewards of the mode. Players should aim to unlock this zone as early as possible by reaching the necessary Inter-Knot Level and completing the associated side quest and Reputation exam. Once unlocked, it serves as a consistent and valuable source of Withered Crystals: Heaven’s Azure, which are essential for activating Combat Configuration—the exclusive Hollow Zero buff system that boosts performance during runs.

To make the most of each week, players should complete Bounty Commissions related to Hollow Zero. These provide essential materials such as Polychromes, Boopons, and Bangboo enhancement items. Players are allowed to refresh and modify Basic Commissions up to two times per week, with the exception of B-rank or higher commissions, which are fixed. Prioritizing Hollow Zero-specific tasks within these bounties can streamline your overall resource gain and progression.

For resource farming, Withered Crystals can be consistently acquired by clearing Old Capital Metro or higher-level Hollow Zero stages. These Crystals serve as the backbone for unlocking buffs through Combat Configuration, making it crucial to regularly farm this zone to maintain a competitive edge in harder stages.

A unique aspect of Hollow Zero exploration is the ability to farm Lost Items from the Old Capital, which are key items used to unlock hidden quests and secret content within the game. These items are found by stepping on special Event squares within Hollow Zero stages, including Old Capital Metro. Some of these squares require spending Gear Coins, with varying amounts like 2,500, 4,500, or even 5,000 coins, depending on the type of event or reward offered.

The Secret Path and Surprise Box Area tiles are the most likely locations where Lost Item events can be encountered. These may appear as distinct, sunken versions of Bangboo tiles, often darker and deeper in appearance, signaling the potential for a hidden reward. Exploring routes that lead through these areas increases the chance of triggering Lost Item events.

A known strategy for Lost Item farming involves repeatedly entering Old Capital Metro, checking the initial tile layout for a potential hidden event, and quitting early if the event does not appear. Repeating this process several times—often every 3–5 runs—has been observed to spawn a Lost Item event. When one is found, it is often more efficient to reset the run immediately rather than complete the entire stage. This strategy also applies when farming Resonia Collection pieces or scouting for other rare Hollow Zero unlocks.

While there was previously a daily limit of three Lost Items, it appears this restriction may have been lifted, allowing players to farm more freely. Additionally, Lost Items can appear in other Hollow Zero zones, not just in Old Capital Metro. If repeated attempts yield no results, transitioning to other areas such as the Construction Zone or Withering Core may help trigger the events. These items are distributed dynamically, so being flexible with your farming location can increase your success rate.

Once Lost Items have been collected, players should speak with Ray at the Scott Outpost Interior, who helps track how many items you’ve found and can trigger Lost Items from the Old Capital quests. These quests often require specific items to advance and may unlock hidden lore, stages, or bonus rewards tied to Hollow Zero’s deeper narrative.

Lastly, some Lost Items from the Old Capital can also be obtained during Inferno Reap events, specifically in stages like “Here It Once Swayed”, offering an alternative method for players actively participating in event content. Combining event play with daily Hollow Zero runs can greatly accelerate collection and progression.

In summary, mastery of Old Capital Metro isn’t just about survival—it’s about optimizing routes, using gear coins wisely, and understanding how event tiles tie into broader content like hidden quests. By managing Corruption carefully and targeting specific objectives like Lost Items, players can make the most of their Hollow Zero experience.