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Echoes of the Past

Last updated 2026-02-22

Echoes of the Past is an Event Commission and part of the main storyline for When Dreams Remain Unfinished in Failume Heights.

Parts

  1. Ether Experiment

Steps

  1. Complete "Light Nap Battle: Troublemaker"
  2. Talk to Dr. Lydia
  3. Ask technician Zane what's going on

Dialogue

Icon Dialogue Event Complete "Light Nap Battle: Troublemaker"

Everything's set! Join forces with your monster companions to defeat Typhon and retrieve the information about Yidhari's parents.
(Light Nap Battle: Troublemaker is selected)
Fairy: Try out the "Auxiliary Plug-Ins"!
Fairy: Go with this one first!
Fairy: Equip the "Auxiliary Plug-In" to enhance your allies' abilities.
(After completing Light Nap Battle: Troublemaker)

Ether Experiment

Special Event
"Ether Experiment"

Story Description: After hacking into Typhon, you discover a video recording from the Darkwater Research Center showing Yidhari's mother rescuing in an experiment. Upon seeing the footage, Yidhari decides not to wake up yet and continue investigating, which everyone agrees to.


Lucia: Let's try to hack in again and see if it works.
Icon Dialogue Talk Try hacking in.
(ProtagonistProtagonist): Wait, (‍let melet me / lemmelemme‍) take a look. This should connect here, and this should connect there...
(ProtagonistProtagonist): It looks like there are some relevant records. Darkwater Research Center, experimental footage, recording conditions...
(ProtagonistProtagonist): Found it! Anti-Corruption Serum Prototype Research... "Yidhari Prototype Medicine Experiment Records."
Yidhari: Can you play it for me?

The screen flickers for a moment, and a segment of the experimental footage begins playing. Judging by the data type, this seems to be a real memory that Yidhari had once experienced.
Angel Murphy: This is Darkwater Research Center, Research Department, Level 1 Researcher Angel Murphy.
Angel Murphy: We're now at hour 27, minute 18 of the experiment. The subject's vital signs are rapidly deteriorating. All safety serums have failed to prevent Ether-induced cellular corruption.
Angel Murphy: Considering the physical strain on the subject, we've suspended the use of primary medication.
Angel Murphy: The subject is projected to develop a core in approximately 12 hours, and will be fully corrupted into an Ethereal within 18 hours...
Angel Murphy: Please, Hari. Mommy is begging you...
Angel Murphy: At 31 hours and 6 minutes into the experiment, the anti-corruption serum, codenamed AVX, was successfully separated and purified using the subject's maternal sample as the base. Come on... hang in there, Hari!
The experiment's footage ends with the sound of Yidhari's mother sobbing...

Yidhari: So, my mother went to great lengths to treat my Ether corruption back then...
Yidhari: But it doesn't seem like it went very well...
(Memory Shard: Treatment added to the Workbench)
Memory Shard: Treatment
Intelligence Memory Shard Treatment
A fragment of Yidhari's memory data extracted from the VR Dream Terminal.
It records how Yidhari's mother tried everything to cure her, but nothing seemed to work, ultimately driving her to the brink of breakdown.
(SiblingSibling): Sorry to interrupt. Yidhari's mental stability has returned to a safe level. Dr. Lydia says we should be able to wake her up with medication.
Yidhari: No, I'm sorry... I'm not ready to leave this dream yet. My parents' disappearance has gnawed at my mind for so long now... I need to find out where the Darkwater Research Center is and what happened there.
Lucia: But where else can we go to investigate? We've already hacked into the highest-level machines.
Yidhari: Port Elpis! These machines all have shipping records from Port Elpis to the Darkwater Research Center.
(SiblingSibling): Uh, are you sure we should continue with the investigation? Perhaps we should wake up first and think things through...
Icon Dialogue Talk Express respect for Yidhari's decision
(ProtagonistProtagonist): Hmm, I still want to respect Yidhari's decision. Let's continue investigating at Port Elpis with her.
Lydia cuts off everyone's dream link and returns to reality for a short rest.

Icon Dialogue Event Tracked Talk to Dr. Lydia

Lydia has ended everyone's dream link and returned to reality for a short break. Go talk to her about Yidhari's condition and the next steps.
Lucia: Phew, finally awake. Maybe I haven't been sleeping enough. That dream felt way too exhausting.
Lydia: Uh, it's not your fault. Normally, people don't have to command Ethereals in their dreams...
Icon Dialogue Talk (‍BelleBelle / WiseWise‍), what's the situation right now?
(SiblingSibling): You gathered two pieces of data from the dream that resemble memories — one of Yidhari being rescued by Pompey in the Outer Ring, and the other about the research at the Darkwater Research Center.
(SiblingSibling): Both memories mention a place near the Outer Ring — the Darkwater Research Center. It must be where Yidhari's key memories lie.
(SiblingSibling): To find the exact location, we'll need to go to Port Elpis and uncover the right passage. Yidhari has already set out for it in her dream.
Lydia: Hmm, my equipment shows that an area resembling Port Elpis is gradually taking shape in the dream. We should be able to continue the investigation tomorrow.
Lucia: Then let's meet here again tomorrow. We'll have the Night Emissary awaken the slumbering Octopus Princess!
Lydia: Oh, right, Senior mentioned he needed to talk to (‍Mr. WiseMr. Wise / Miss BelleMiss Belle‍) about something. If you've got time later, go check in with him.
Icon Dialogue Event Tracked Ask technician Zane what's going on

Zane, an HIA technician and Lydia's senior, seems to have something to discuss. Go check in with him.
(Talk to Yidhari, optional)
Yidhari: (‍Wise...Wise... / Belle...Belle...‍)
Yidhari: ...
(Talk to Zane)
Zane: Well, well, Master Proxy.
Zane: I just saw your performance in the Dream Terminal — truly breathtaking! My admiration for you flows like an endless river...
Icon Dialogue Talk Umm... If you have something to say, say it.
Zane: Ah. Well, watching you enter dreams and command Ethereals in battle inspired me — it's given me a new direction for my research.
Zane: Previously, all VR combat data was based on humans. But data on battles between Ethereals and machines is actually very scarce.
Zane: So I've modified some of the combat data to simulate battles with Ethereals, but I still need a tester... Would you be interested?
Zane: Of course, this isn't just for me. The stability data we gather will also help steady Yidhari's brainwaves. I've prepared some compensation for you.
Icon Dialogue Talk For Yidhari, I'm in.
Icon Dialogue Talk For the reward, I'm in.
Zane: Much appreciated!! The test entry point's already linked to the VR Dream Terminal — you can jump in and start testing anytime! Even right now!
Icon Dialogue Event Alright then, let's see how this test works.
Icon Dialogue Talk Wait, there's something else.

(Bubble, upon entering the VR Dream Terminal)
Fairy: Master, high-difficulty mode Simulation Challenge has been successfully connected to the terminal.
Fairy: Get bonus rewards by achieving a Perfect Completion!
Fairy: Tap hereTap here/Click hereClick here/Press Controller LSPress Controller LSTooltip for Press 24px|alt=Controller LS|link= to view the Perfect Completion conditions in detail

Other Languages

LanguageOfficial Name
EnglishEchoes of the Past
Chinese
(Simplified)
前尘幻梦
Chinese
(Traditional)
前塵幻夢
Japanese過去の幻
Korean지난날의
Jinannarui Kkum
SpanishQuimeras del pasado
FrenchÉchos du passé
RussianСны о прошлом
Sny o proshlom
Thaiความฝันในอดีตกาล
VietnameseẢo Mộng Quá Khứ
GermanEchos der Vergangenheit
IndonesianMimpi Masa Lalu
PortugueseSonhos do Passado

Change History