The Never-Ending Arachne Complete Guide: Eternal Waltz Arc, Chaos Weakness, Dark Room Light Circle Mechanic, Discord Team

Quick answer: The Never-Ending Arachne is at the Ebisu Auction House on the Shore of the Unheard-Of, weakness Chaos. Unlocked by clearing the main quest “Deal? Deal!” + enters the Anomaly Pilgrimage weekly. It teleports + spams AoE, making sustained DPS hard. Phase 2 dark room light circle mechanic (step into the dark and you freeze) + a must-parry final slash. Your first weekly clear guarantees the Eternal Waltz S Arc (Fadia signature weapon). Discord team: Daffodill + Baicang + Sakiri + Fadia.

ℹ Note: the name comes from Arachne, the weaver of Greek myth (turned into a spider for challenging Athena’s weaving skill) — fitting the auction house’s opulent stage theme and the Arc name “Eternal Waltz.” The element is written uniformly as “Chaos” (this is the in-game name of that element).

The spider Anomaly drawn out by sneaking into the Ebisu auction — The Never-Ending Arachne is a main-story finale-tier boss + Anomaly Pilgrimage weekly, and it drops Fadia’s free signature weapon “Eternal Waltz.” This guide rounds up the location, moveset, Phase 2 dark room, and Discord team all in one place.

1. What Is The Never-Ending Arachne

Item	Details
Chinese / English name	永不謝幕的阿拉克涅 / The Never-Ending Arachne
Type	Boss-tier Anomaly, spider theme
Combat traits	High HP, high attack frequency, teleports, lots of AoE attacks — making it very hard to keep up steady DPS (the trickiest part)

2. Location and Unlock

• Location: Ebisu Auction House, on the Shore of the Unheard-Of (region name per the in-game text). Once unlocked, walk up to the auction house entrance to re-challenge it
• Unlock quest: clear the main quest “Deal? Deal!”
• ⚠️ Chapter correction: most English sites (Game8 / GameWith) list it as Chapter 3, not Chapter 2 — best to just remember the quest name and treat the chapter number as per in-game
• Story: you sneak into the high-end Ebisu auction with Stri Express to help Hotori bid using “smooth talk” and “raising the price”; a key item gets stolen, triggering a security Anomaly → which draws out Arachne
• Weekly: after clearing it, you enter the Anomaly Pilgrimage weekly rotation

3. Element and Weakness

• Weakness: Chaos — written uniformly as “Chaos,” don’t write “Dark” to avoid confusion
• Resistances: no special resistances listed

4. Moveset (Complete)

Phase 1

Move	How to handle
AoE shockwave	Dodge / Critical Dodge out when it gets close
Lock-on laser (three tracking beams)	Keep running to break away and avoid them
Four-hit combo + shockwave	The fourth hit fires a shockwave too; the third hit is parryable, so cleanly dodge the first two and aim your counter at the third
Lunging four-hit combo	Hard to deal with if you whiff the parry — break away to create distance
Close-range combo	Can trigger Critical Riposte repeatedly, but it’s mixed with fast attacks that have no tell
Moving shockwave	The boss circles while firing; you can jump over it, and it’s best to stay close and go for Critical Riposte

⚠️ General rule: normal slashes often go 3-4 hits before stopping, and not every hit has a red flash tell — don’t assume it’s over after the first hit.

Phase 2 (story battle exclusive)

• ⭐ Dark room / light circle mechanic (core): the arena goes dark, and you can only act while inside a light circle; stepping into the dark freezes you in place. You must keep moving within the lit zones while dealing with attacks
• ⭐ The always-parryable final slash: Phase 2 is mostly normal attacks + parryable attacks. Be sure to watch for the “final slash” — it can always be parried; a successful parry briefly weakens Arachne = your main DPS window

Phase move	How to handle
Laser + shockwave	Ground laser and shockwave come at the same time; retreat first if you’re low on HP
Rapid-fire laser / full-screen laser	Read the warning prediction lines clearly — there are safe gaps between the lines, so slip through the gaps

Parryable vs Dodge-Only

• ✅ Parryable: the third hit of the four-hit combo, various combo finishers, the Phase 2 final slash
• ❌ Only run / dodge / jump: the three tracking lasers (run away), full-screen laser (slip through the gaps), ground shockwave (jump or Critical Dodge)
• ⭐ Mechanic payoff: parrying and dodging contribute far more to staggering than tanking the hit; a clean parry also instantly fills your Cycle Energy bar — save your big skills for the stagger/break stun and then unload

5. Drop Rewards

Eternal Waltz — S-rank Synthesis Arc, Fadia’s signature weapon, free

• How to get it: guaranteed drop on your first weekly clear; repeating the weekly afterward only produces materials, not the Arc again. The shop’s “Arc Selection Store” lets you exchange for it with Tri-Keys
• Stats: S-rank, base ATK 28, sub-stat HP; passive “Arachne”: Lv1 Max HP +20%, Psyche DMG +10% for 10 seconds after casting your Ultimate; Lv5 HP +32% / Psyche DMG +18%
• Best fit: Fadia — she spends HP, tanks damage, and her Ultimate deals Psyche DMG, pairing perfectly with the passive

For full Arc details, see the Fadia Complete Build Guide.

Weekly Reward (spend stamina to claim)

• Claim mechanic: each settlement costs 60 stamina (Character Pixels)
• Rewards: Hunter EXP, Scarab Coins, Advanced Hunter’s Guide, Colorless Dye, Vanity Cuffs (character skill upgrade material), Arcane Thread / Magic Thread
• ⭐ Priority: one of the highest-priority Anomaly Pilgrimage weeklies — it produces Esper Ability upgrade materials, which gate every character’s late-game power; the rotation pool also includes Morphix

6. Recommended Teams (Chaos Weakness)

⚠️ Fadia and Haniel are an either-or pick for the same slot (Psyche), and the real Scorch source is Baicang / Adler (Incantation).

Core: Daffodill as Main DPS + triggering Discord (one of the best stagger setups in the game):

• Scorch source: Daffodill (Chaos) + Adler / Baicang (Incantation) → triggers Scorch
• Nova source: Daffodill (Chaos) + Fadia or Haniel (Psyche) → triggers Nova
• Scorch + Nova on the same target at once → triggers Discord

Sample Team ⭐

Daffodill + Baicang + Sakiri + Fadia (which also farms the signature weapon)

Scorch DoT Variant

Daffodill + Baicang + Sakiri + Adler

Typical rotation: Baicang opens by laying down Scorch → Daffodill charges the Cycle bar → at full bar swap to Haniel to cast Nova (if the target is still under Scorch this triggers Discord) → swap back to Daffodill to keep staggering.

7. Combat Tips + Common Beginner Mistakes

Tips

1. Phase 2 dark room light circle: treat “stay in the light” as your top priority — better to skip a hit than to walk into the dark and get frozen
2. Final slash parry: throughout Phase 2 watch for the “finishing slash” — it’s always parryable → after a successful parry the boss is briefly weakened → immediately unleash your Ultimate and heavy skills
3. Parry > tanking hits: parrying / dodging contributes far more to staggering than eating the hit, and a clean parry instantly fills the Cycle Energy bar
4. Don’t try to dodge through lasers: for the three tracking lasers, “running” is the most reliable; for the full-screen laser, “find the gap between the prediction lines and slip through”

Common Beginner Mistakes

❌ Mistake	Consequence
Walking into the dark in Phase 2	You get frozen and eat a full combo for nothing
Rushing to counter the first basic-attack hit	Basic attacks often go 3-4 hits, and not every hit has a red flash
Trying to roll through the full-screen laser	You should find the gap between the prediction lines instead
Expecting a second Arc from re-farming	Eternal Waltz only drops on your first weekly clear; afterward you only get materials
Writing Chaos as “Dark” and using the wrong element	Make sure your team actually counters with Chaos

8. Related Guides

• Complete Anomaly Boss Bestiary — overview of all 18 bosses
• Serenetti / Mammon / Headless Rider / Beat King / Nestbound Bird / Black Tome — other popular bosses
• Fadia Complete Build Guide — the owner of Eternal Waltz
• Daily / Weekly Checklist — planning the Anomaly Pilgrimage weeklies
• Cycle Energy Reaction System — Discord / Scorch / Nova reactions

FAQ

Arachne data compiled from Game8, GameWith, TheGamer, VPEsports, Nerdschalk, AllThings.How, Sportskeeda, Bahamut, Entertainment Taxi, 4Gamers, and other public sources. The unlock chapter (most list Chapter 3), region name translations, move names, and stamina resource names are per the in-game text.