There is a certain kind of Wuthering Waves player who looks at a giant, glowing, mildly furious bird and thinks, "Yes. I would like that bird to live inside my character." That player is correct, and the bird in question is the Nightmare Mourning Aix — a 4-Cost Echo that has quietly become one of the most sought-after trophies in Rinascita. It hits hard, it buffs Spectro, and it does all of this while looking like it has personally been wronged by the universe.

Nightmare Echoes, as a whole, are a step above the 4-Cost Echoes players spent months farming back in Huanglong. Tougher to fight. Meaner to look at. Considerably more rewarding. At the time of writing, only seven of them exist in the game, which means collectors have a small, precious menu to work through — and the Mourning Aix sits near the top of it.

Step One: Talk to a Cat. Seriously.

Here is the part that trips people up. Nightmare Echoes are not simply lying around waiting to be punched. Every single one of them is locked behind a quest, and no amount of aimless wandering around Rinascita will fix that.

Players need to complete the Dream Patrol I quest in Rinascita. Before that becomes possible, they must also finish Act 2, Chapter 3 of Rinascita's Main Story Quest. Once both boxes are ticked, a rather unassuming White Cat becomes the most important NPC in the region.

The cat hangs around Ragunna City, southeast of the Ragunna City Resonance Nexus, sitting politely in front of a purple frame. It is perched on a terrace, so the player has to climb a few buildings to reach it — which, frankly, is a very normal thing to do in service of a cat. Speak to it once, and every Nightmare Echo in the game unlocks at once. No grinding. No offerings. Just a chat.

Step Two: Fly South and Pick a Fight

The Mourning Aix makes its home in the southernmost slice of Rinascita: Averardo Vault. Anyone who has already activated the southernmost Resonance Beacon is in luck — teleport there, glide down, and the boss will be waiting in its arena like a landlord who heard the rent was late.

It is worth being honest about the difficulty curve. Nightmare Echoes are noticeably nastier than their standard counterparts, and the Mourning Aix is no exception. Players who stroll in under-geared will get a firsthand education in why the word "nightmare" was chosen.

Step Three: Decide Who Deserves the Bird

Not every character wants a Spectro-flavoured nightmare chicken on their build. The shortlist is short, and it looks like this:

Character	Why It Works
Phoebe	A natural fit if she is being built as a Spectro DPS
Rover (Spectro)	The other obvious home for it, assuming a damage-focused setup

That is it. Two names. The Mourning Aix is a specialist, not a crowd-pleaser, and players who try to force it onto a mismatched character will find their damage numbers shrugging apologetically.

What the Echo Actually Does

Equipping the Nightmare Mourning Aix lets the player summon the creature itself, dealing Spectro DMG to whatever is unfortunate enough to be standing nearby. More importantly, it increases Spectro DMG against enemies suffering from Spectro Frazzle — which turns a decent Echo into a genuinely threatening one.

For Sonata effects, Eternal Radiance is the recommended pick. Its substat boosts CRIT Rate under the right conditions, and for characters like Phoebe or Spectro Rover who are being pushed toward pure damage output, that is exactly the sort of thing that makes bosses reconsider their career choices.

The Short Version

For anyone who skipped ahead — and honestly, fair — here is the whole process compressed into something tweetable:

1. 🐱 Complete Dream Patrol I and finish Act 2, Chapter 3 of the Rinascita main story.

2. 🗺️ Find the White Cat southeast of the Ragunna City Resonance Nexus and talk to it.

3. 🕊️ Teleport to Averardo Vault and beat the Mourning Aix in its arena.

4. 💜 Slot it onto Phoebe or Spectro Rover with an Eternal Radiance build.

It is a lot of flying, one slightly strange conversation with a feline, and one very loud bird. But the payoff is a 4-Cost Echo that pushes Spectro characters into genuinely frightening territory — and in a game where every percentage point of damage matters, that is a trade most players will happily make.

Besides, who among us has not climbed a building in Ragunna City just to talk to a cat?