Umbral Monument
Endfield's Permanent Endgame Mode — Series 4: Turbidity Manifest
Last updated: 2026-05-09
Complete guide to Umbral Monument in Arknights: Endfield, featuring the current 4th series — Turbidity Manifest. Covers unlock requirements, all six Turbidity Manifest stages, Normal vs Agony modes, deep-dive guides for Stages 3, 5, and 6, recommended team compositions, and the Monumental Etching: Corrupting Surge event rewards (May 8 – May 22, 2026).
* TL;DR - Key Points
- * Permanent Endgame Mode -- New series rotates in roughly every 6-8 weeks
- * Unlock: Complete Paving the Way + Authority Level 30
- * 4-Operator Teams -- Each stage limits you to 4 operators
- * Current Series 4: Turbidity Manifest -- Launched May 8, 2026, six stages, water-themed enemies
- * Normal & Agony Modes -- Clear Normal to unlock Agony (tacticals banned)
- * Stage 6 Agony Twist -- Every successful enemy hit applies Solidification (freeze)
- * Monumental Etching: Corrupting Surge -- Bonus event runs May 8 – May 22, 04:00 server time
Video Guides
Full-run video walkthroughs for the Turbidity Manifest series — Stage 3 (Tidal Grief), Stage 5 (Blood Debased), and Stage 6 (Cryostatic Connection) with commentary.
Turbidity Manifest Video Guides
Tidal Grief Stage 3: Ardelia Solo Cheese
1 weeks ago
Blood Debased Stage 5: Turbidity Manifest Guide
1 weeks ago
Cryostatic Connection Stage 6: Turbidity Manifest Guide
1 weeks ago
Contents
What is Umbral Monument?
Umbral Monument is Arknights: Endfield's permanent high-difficulty endgame combat mode, originally released February 12, 2026. It is designed for players who have completed the main story progression and want challenging content that tests team building and combat execution. New themed series rotate into the same hub every 6-8 weeks — the current rotation is the 4th series, Turbidity Manifest.
Permanent Mode
Past series stay accessible permanently. Only the bonus event reward windows are time-gated.
Series System
Each themed series brings new stage mechanics. So far: Those Forsaken by the Land, Inorganic Construct, Searing Scars, and Turbidity Manifest.
4-Operator Teams
Each battle is limited to 4 operators. Every slot matters -- bring the right tools for each stage's mechanics.
Medal System
Earn Engraved Medals for clearing a series in Normal. Trimmed medals require all-Agony clears -- the ultimate flex.
Pro Tip: Check Enemy Intel
Before starting a stage, check the Enemy Intel button in the stage selection screen. It shows enemy types, resistances, and attack patterns — essential for building the right team for each Turbidity Manifest stage. For full enemy rosters across every series (Normal Lv 60 and Agony Lv 90 tiers), see the Umbral Monument Database.
How to Unlock
1. Complete Paving the Way
Finish the main mission Chapter I Process II: Paving the Way. This is a story progression requirement that ensures you have completed the main campaign before tackling endgame content.
2. Reach Authority Level 30
Earn Operational EXP by spending Sanity, completing missions, and finishing daily tasks. Authority Level 30 represents significant account progression and ensures you have the resources to build competitive teams.
Current Series: Turbidity Manifest (Series 4)
The Turbidity Manifest is the fourth Umbral Monument series. Six stages of escalating water- and corruption-themed challenge, launched May 8, 2026. The deep-dive guides below cover Stages 3, 5, and 6.
Series Timeline
Series 1: Those Forsaken by the Land · Series 2: Inorganic Construct · Series 3: Searing Scars · Series 4: Turbidity Manifest (current)
Launch
May 8, 2026, 12:00 server time across all regions. Stages remain permanently playable.
Event Window
Monumental Etching: Corrupting Surge runs May 8 – May 22, 04:00 server time. Bonus Oroberyls vanish after the event closes.
Six Stages
Each stage has Normal (Lv. 60) and Agony (Lv. 90, no tacticals) modes. Clear all six in Agony for the trimmed medal.
Equal Resistances
Most enemies share resistances across elements — your most-built team is your best team. No off-element scramble required.
Six-Stage Overview
| Stage | Theme | Guide |
|---|---|---|
| Stage 3 — Tidal Grief | Solo-cheeseable, crystal-defense gimmick | Ardelia Solo Cheese → |
| Stage 5 — Blood Debased | Imbued Quillbeast boss + endless add spawns | Imbued Quillbeast Guide → |
| Stage 6 — Cryostatic Connection | Tidalklast boss, freeze-buff stagger loop | Tidalklast Guide → |
Stage 3: Tidal Grief
Stage Mechanic: Crystal Defense
Blue goos spawn from 24 points and march toward a central crystal. If they pile up there, they detonate together — an unsurvivable damage spike. Win condition is spatial control, not raw DPS.
Ardelia Solo Cheese — Key Points
- * Solo Ardelia run — no other operators in the squad.
- * Lynx set is mandatory — the treatment bonus turns Ardelia's self-heals from "decent" into "literal wall."
- * Push goos away from the central crystal — spread the damage across time.
- * Bank 3 ATB bars before the 8/24 and 12/24 enemy spawn waves.
- * Save Ardelia's ult for the 12/24 wave — the breakpoint where the run lives or dies.
Stage 5: Blood Debased
Stage Mechanic: Add Spam
The Imbued Quillbeast summons regular Quillbeasts on a timer, with the spawn rate ramping up at low boss HP. Lock onto the boss, let your AoE clean the trash, and interrupt the lava-spit charge.
Recommended Teams
Zhuang Fangyi (Electric AoE)
Perlica + Fangyi + Arclight + Antal/Alesh — high-stack AoE turns add spam into free damage stacks.
Yvonne (Cryo Freeze)
Yvonne + Xaihi + Gilberta + Tangtang — Solidification locks adds, Yvonne ults the boss in peace.
Laevatain (Heat Brute Force)
Laevatain + Akekuri + Wulfgard + Ardelia — massive AoE doesn't care how many adds spawn.
Core Loop
- * Tunnel the Imbued Quillbeast — chasing adds wastes damage cycles.
- * Save SP for the lava-spit charge — interrupt the inflate animation for massive Stagger.
- * Use the boss as a shield — position so its body soaks the regular Quillbeasts' projectiles.
Stage 6: Cryostatic Connection
Stage Mechanic: Freeze-Buff Damage Reduction
The Tidalklast hardens its body with ice to gain massive damage reduction. DPS-racing the buff is throwing damage into a wall — the win condition is interrupting its charging animations to build Stagger, then dumping ultimates in the open window.
Recommended Teams
Mono Physical (Best Answer)
Endministrator + Pogranichnik + Chen Qianyu + Lifeng — high base Stagger + Swordmancer Set punches through the buff phase.
Yvonne Cryo (Safe Ranged)
Yvonne + Tangtang + Xaihi + Gilberta — stay out of melee, dump ult during Stagger. Xaihi cleanses Solidification.
F2P Endministrator
Endministrator + Akekuri + Chen Qianyu + Ardelia — budget Mono Physical with Ardelia as the sustain swap.
Core Loop
- 1. Dodge the boss's attacks during the buffed phase.
- 2. Save skills/ults for its charging animations.
- 3. Interrupt to pump Stagger gauge — Chen's Momentum Breaker adds +10 per interrupt.
- 4. Break the buff when the gauge fills.
- 5. Dump damage in the open window before it re-freezes.
Xaihi Is Your Cleanse Button
Xaihi's ultimate dispels Cryo Inflictions and Solidification across the team. Save it for emergencies in Agony — the moment an operator gets frozen, ult Xaihi to break the chain wipe before the auto-swap puts another operator into the freeze zone.
Difficulty Modes
Normal Mode
- -- Tacticals allowed during combat
- -- Recommended Lv. 60
- -- Practice stages and learn mechanics
- -- Required to unlock Agony mode
- -- Rewards: First-clear items, Engraved Medal
Agony Mode
- -- Tacticals prohibited
- -- Lv. 90 enemies, significantly harder stats
- -- Stage 6 twist: Enhanced enemy DMG instantly applies Solidification on hit
- -- More aggressive boss patterns and lower margin for sloppy positioning
- -- Rewards: Trimmed Engraved Medal
Critical Warning: Always practice a stage in Normal mode before attempting Agony. Agony mode requires perfect execution and punishes mistakes severely — especially Stage 6, where a single missed dodge can chain-freeze your entire team.
Rewards
First-Clear Rewards (One-Time)
| Reward | Purpose |
|---|---|
| Mark of Perseverance | Profile medal — trimmed version for full Agony clear |
| T-Creds | Standard currency |
| Advanced Cognitive Carrier | Character ascension material |
| Arms INSP Set | Weapon upgrade materials |
| Protohedron | Rare crafting material |
Medal Rewards
Engraved Medal
Awarded for completing all six Turbidity Manifest stages in Normal mode. Shows you've cleared the current series.
Trimmed Engraved Medal
Upgraded version awarded for clearing all six stages in Agony mode. The ultimate proof of mastery for this series.
Monumental Etching: Corrupting Surge
Limited-time event running alongside the Turbidity Manifest. Event window: May 8, 12:00 – May 22, 04:00 server time. Stages remain permanent after the event closes, but the bonus Oroberyl rewards do not.
| Challenge | Reward |
|---|---|
| Clear each stage once | 150 Oroberyls |
| Participate in Agony Mode 5 times | 150 Oroberyls |
| Deal 500,000 damage | 150 Oroberyls |
| Deal 1,500,000 damage in Agony | 150 Oroberyls |
| Enter stages multiple times | 150 Oroberyls each |
Pro Tip: Manual Claim Required
Monumental Etching rewards are NOT automatically claimed. Visit the in-game event page after every Umbral Monument session and claim your Oroberyls. After May 22, the bonus rewards vanish even though the stages stay permanently playable.
Team Building Strategy
Essential Roles
1. Main DPS
Your primary damage dealer. Laevatain, Yvonne, Zhuang Fangyi, or Endministrator.
2. Healer
Mandatory for Agony. Ardelia, Gilberta, Xaihi, or Ember.
3. Sub-DPS/Support
Secondary damage or buffs. Wulfgard, Perlica, or Akekuri.
4. Flex Slot
Adapt to stage needs — Chen Qianyu for Stagger interrupts on Stage 6, Tangtang for AoE control on Stage 5.
Elemental Considerations
Heat (Combustion)
Good sustained damage. Slight C-tier resistance on Quillbeasts but Laevatain shrugs it off.
Electric (Electrification)
Arts DMG Taken debuff. Zhuang Fangyi AoE shines on Stage 5's Quillbeast spam.
Nature (Corrosion)
Resistance reduction. Rare and valuable team-wide buff.
Cryo (Solidification)
Freeze CC on adds. C-tier resist on Tidalklast (Stage 6) — Yvonne still works during Stagger windows.
Physical Teams
Physical teams (Crush/Breach) are self-sufficient and don't require other elements. They consume Vulnerability stacks for massive burst damage. Mono Physical is the strongest answer to Stage 6's Tidalklast thanks to its Stagger output.
Arts Intensity Priority
Arts Intensity scales reaction damage:
-- 100 Arts Intensity = 100% bonus damage to reactions
-- Also improves amplification effects (Electrification, Corrosion, Breach)
-- Diminishing returns past 100 on amplification
-- Characters who apply reactions should prioritize this stat
Common Mistakes & How to Avoid Them
1. Skipping a Healer in Agony
Agony bans tacticals and consumables — your only sustain comes from operator kits. Solution: Always include Ardelia, Gilberta, Xaihi, or Ember in your Agony team. Stage 3's solo cheese is the only exception (and even that runs Ardelia).
2. DPS-Racing the Tidalklast (Stage 6)
The freeze-buff phase has chunky damage reduction — face-tanking it is throwing damage into a wall. Solution: Wait for the Staggered window. Hit the ice refrigerator only after you've broken the buff.
3. Chasing Adds on Stage 5
The regular Quillbeasts have low HP and die to AoE splash anyway. Switching targets wastes your damage cycles and lets the boss free-cast its lava spit. Solution: Tunnel the Imbued Quillbeast and let your AoE handle the trash.
4. Using the Same Team for Every Stage
Each stage favors different compositions. Stage 5 wants AoE, Stage 6 wants Stagger control, Stage 3 is solo. Solution: Rebuild your roster between stages — operators aren't locked after use.
5. Attempting Agony Without Practice
Agony bans tacticals and significantly increases difficulty. Solution: Clear Normal first to learn enemy patterns. Don't waste Agony attempts on blind runs — Stage 6's chain-freeze will end your team in seconds if you don't know the tells.
6. Forgetting to Claim Event Rewards
Monumental Etching: Corrupting Surge rewards are not automatically claimed and expire May 22 at 04:00. Solution: Check the event page after every session and claim your Oroberyls immediately.
Quick Reference Checklist
Frequently Asked Questions
What is the Turbidity Manifest in Arknights: Endfield?
The Turbidity Manifest is the fourth Umbral Monument series, launching May 8, 2026 at 12:00 server time. It introduces six stages (Normal and Agony) themed around water-corrupted creatures, including the Imbued Quillbeast on Stage 5 and the Tidalklast on Stage 6. The series is permanent, but its bonus event window (Monumental Etching: Corrupting Surge) closes May 22 at 04:00 server time.
When does Umbral Monument unlock?
Umbral Monument unlocks after completing Chapter I Process II: Paving the Way and reaching Authority Level 30. Each new series (currently the 4th, Turbidity Manifest) is added to the same Umbral Monument hub — once unlocked, you have access to every series.
What's the difference between Normal and Agony in the Turbidity Manifest?
Normal mode is Lv. 60-recommended and allows tacticals and consumables. Agony mode is Lv. 90, bans tacticals and consumables, and adds series-specific twists — most painfully on Stage 6 (Cryostatic Connection), where every successful enemy hit instantly applies Solidification, freezing the operator. Clear all six stages on Agony for the trimmed medal.
Can I solo Stage 3: Tidal Grief?
Yes — Tidal Grief is solo-cheeseable with Ardelia in a full Lynx set. The stage's failure condition is geometric (blue goos piling on the central crystal), not raw DPS, so spatial control + Ardelia's self-heal + the Lynx treatment bonus is enough to outlast the run. Bank ATB before the 8/24 and 12/24 spawn waves and save Ardelia's ult for 12/24.
Why does Yvonne work on Stage 6 if Tidalklast resists Cryo?
The C-tier Cryo resistance is real, but Yvonne's burst windows hit during the boss's Staggered phase (when its ice-buff damage reduction drops). Her single-target damage in that window is high enough to compensate for the resistance. Pair her with Xaihi — whose ultimate cleanses Cryo Inflictions and Solidification team-wide — for an Agony-safe ranged comp.
How do I get the Monumental Etching: Corrupting Surge Oroberyls?
The event runs May 8 – May 22, 04:00 server time. Complete challenges (clear stages, enter Agony mode 5 times, deal damage thresholds, repeat-enter stages) to earn 150 Oroberyls per task. Rewards must be claimed manually from the in-game event page — they are not automatic, and after May 22 they vanish even though the stages remain permanently playable.
Turbidity Manifest Stage Deep Dives
Turbidity Manifest Series Overview
Launch breakdown, six-stage framing, prep checklist, and the limited-event reward window in detail.
Stage 3: Tidal Grief — Ardelia Solo Cheese
Solo YOLO with Lynx-set Ardelia. ATB management at 8/24 and 12/24 spawn waves.
Stage 5: Blood Debased — Imbued Quillbeast
AoE-friendly comps for Zhuang Fangyi, Yvonne, and Laevatain. Tunnel the boss, AoE the adds.
Stage 6: Cryostatic Connection — Tidalklast
Mono Physical and Yvonne Cryo team comps. Stagger the freeze-buff, dump damage in the open window.
Umbral Monument Database
All battle stages across every rotation with enemy rosters at Normal (Lv 60) and Agony (Lv 90) tiers — boss and elite portrait catalog included.
Series 2 Archive: Inorganic Construct Best Teams
Stage-by-stage team builds for the Inorganic Construct series — still permanent, still farmable.