Hollow Zero: Cleanse Calamity - Zenless Zone Zero - Version 1.5

"Hollow Zero: Cleanse Calamity" is a limited-time event in Zenless Zone Zero (ZZZ) introduced with Version 1.5, "Astra-nomical Moment," which launched on January 22, 2025. This event expands the Hollow Zero endgame mode, specifically within the "Lost Void" gameplay segment, and runs from February 17, 2025, 10:00 (server time) to March 3, 2025, 03:59 (server time)—meaning it ends tonight, March 2, 2025, in most time zones relative to your current date of March 2, 2025. Below is a detailed guide to help you navigate and succeed in this event.
Event Overview
Unlock Requirements:
Complete the Agent Story "Mole in the Hole (I)" to unlock Hollow Zero and Lost Void.
Finish one "Battlefront Purge" investigation in Lost Void to access the "Perpetrator Battle" mode introduced in this event.
Location: Access via Scott Outpost’s HDD System (inside the tent, left of the entrance).
Premise: After thwarting Geppetto’s descent in prior updates, the Defense Force tasks you with eliminating lingering Ethereal threats in Hollow Zero. Speak to Roland at the Outpost to start the event commission "Cleanse Calamity."
Gameplay: Perpetrator Battle
Core Mechanic: This mode pits you against powerful bosses in instanced combat arenas within Lost Void. You must use designated trial Agents provided by the event, each equipped with unique Gear, Resonia, and Tactical Enhancements.
Structure: Four stages, each with two difficulty levels—Low Activity (easier) and High Activity (harder). Completing both difficulties per stage is required for full rewards.
Stages and Agents:
Slumber Hunt - Ellen Joe (Ice Attack)
Lunar Flare - Tsukishiro Yanagi (Electric Anomaly)
Disaster Purge - Hoshimi Miyabi (Ice Anomaly)
Starlight Flash - Billy Kid (Physical Attack)
Ratings:
S-Rank: Clear within 120 seconds (2 minutes).
A-Rank: Clear within 180 seconds (3 minutes).
B-Rank: Clear beyond 180 seconds.
S-Rank is the target for maximum rewards, but A-Rank still contributes significantly.
Strategies and Tips
Trial Agents: You cannot use your own characters. Trial Agents come pre-built with optimized Drive Discs, W-Engines, and stats (typically Level 50, high-tier gear). Familiarize yourself with their kits:
Ellen: High Ice DPS with charged attacks; dodge-counter focused.
Yanagi: Electric Anomaly with EX Special spam; builds Disorder quickly.
Miyabi: Ice Anomaly with combo chains; excels at crowd control.
Billy: Physical DPS with rapid-fire attacks; straightforward but squishy.
Gear and Resonia: Each Agent has unique event-specific buffs:
Ellen’s Gear boosts Ice DMG on dodge-counters.
Yanagi’s Resonia enhances Electric Disorder stacks.
Miyabi’s Tactical Enhancements amplify combo finishers.
Billy’s Gear increases crit rate during burst phases.
Combat Tips:
Dodge Ethereal attacks to avoid stuns and Corruption buildup (though Pressure/Corruption mechanics are less emphasized here than in Withered Domain).
Chain attacks with Bangboo assists (mapped to your Ultimate key) for bonus damage.
Focus on boss weak points—most have telegraphed phases (e.g., Lunar Flare’s AOE bursts).
For S-Rank, optimize DPS uptime; skip unnecessary movement and master Perfect Dodges.
Difficulty Spike: High Activity modes feature tougher bosses with additional mechanics (e.g., Disaster Purge’s multi-phase Ethereal). Practice on Low Activity first.
Rewards
Total Exclusive Rewards:
Polychrome: 160 (40 per stage, all difficulties cleared).
Specialized Chips: 2 Physical, 4 Freeze, 2 Shock (for character ascension).
Senior Investigator Logs: 16 (EXP material).
W-Engine Energy Modules: 8 (W-Engine upgrades).
Bangboo System Widgets: 8 (Bangboo upgrades).
Inter-Knot Credit: 600.
Denny: 160,000.
Claiming: Rewards are tied to first-time clears and rating achievements. After March 3, 2025, 03:59 (server time), limited-time rewards expire, but Perpetrator Battle remains playable without rewards.
Event Commission: Cleanse Calamity
Steps:
Talk to Roland at Scott Outpost.
Complete all four Perpetrator Battles (Slumber Hunt, Lunar Flare, Disaster Purge, Starlight Flash).
Story Context: Ties into the ongoing Hollow Zero narrative, with Belle/Wise and Roland discussing the aftermath of Version 1.4’s events.
Post-Event
After the event ends tonight, the Perpetrator Battle mode persists as a permanent Lost Void feature, allowing you to replay stages with trial Agents for practice or fun, though without the Polychrome and material rewards.
Final Notes
Time Crunch: As it’s March 2, 2025, you have hours left before the cutoff (03:59 server time, likely UTC+8, so adjust for your timezone). Prioritize Low Activity clears for all stages if you’re short on time, then push for High Activity S-Ranks.
Community Sentiment: Posts on X and Reddit suggest some players struggled with S-Rank timings (e.g., 2:14 vs. 2:00), but trial Agents’ superior gear often outperforms personal builds. Experiment with both if you’ve got time.
This event blends Hollow Zero’s roguelike roots with a focused boss-rush twist, making it a rewardi