Defeat the Marble Aggelomoirai in Arknights: Endfield! Our Undying Cinders boss guide breaks down both phases, attack patterns, and how to safely counter her humanoid form.
Table of Contents
| Previous / Next Story | |
|---|---|
| Frontline Rush | Temporary Peace |
Undying Cinders Overview and Rewards
| Story Category | Chapter 1, Process 4 — Smoking Embers |
|---|---|
| Location | Valley IV, Power Plateau |
| Unlock Conditions | Clear “Frontline Rush” |
| Rewards | Origeometry ×2 T-Creds ×5,050 Protoprism ×9 Intermediate Combat Record ×16 Arms INSP Kit ×12 Operational EXP ×300 |
Undying Cinders Walkthrough
Undying Cinders Walkthrough Chart
Talk to Perlica

Before anything else, unlock the Teleport Point sitting right next to Perlica. You'll want to have a fast travel option to this location later on. When you're ready, talk to Perlica.
Level Up and Upgrade Gear
Don't choose I'm ready until you actually are. This is your last opportunity to check your gear sets, level up skills, and make sure each party member is equipped before the fight locks in.
How to Beat Marble Aggelomoirai

This boss excels at sweeping and AoE attacks. Be prepared to dodge a lot in this battle or better yet, use a ranged character to stay clear of her attacks.
No Checkpoints
If you die at any point in Phase 1 or Phase 2, you restart the entire fight from the very beginning. There are no auto-saves in this boss fight. Come prepared.
Marble Aggelomoirai Has 2 Phases

The Marble Aggelomoirai is a two-phase fight with very different rules for each half. This boss doesn't hit especially hard if you're moving properly, but the fight is long enough that mistakes can accumulate.
If your team is struggling, the single best thing you can do before re-attempting is equip a full gear set on every party member, level them up, and upgrade their skills. Higher raw damage output will make things easy for you here.
Phase 1: Destroy the Aggeloi Appendages
The Marble Aggelomoirai is fully immune during Phase 1. You cannot damage her directly. Instead, four Aggeloi appendages will appear. Destroy them one by one to build up her stagger meter and eventually expose her core.
The Process Repeats
If you can't finish the core before the stagger runs out, the process repeats, but only two appendages spawn the second time around. Clear them, and use that second window to finish the job.
Phase 2: The Humanoid Form
Phase 2 changes everything. The Marble Aggelomoirai sheds her stationary form and becomes a six-armed humanoid, airborne, aggressive, and genuinely dangerous. Most of her damage comes from above, so the rule here is simple: wait for a combo to finish before unleashing your attacks and combo skills.
Humanoid Form Attacks
Opening Slam and Sweep
She opens Phase 2 by jumping into the air, slamming down her weapon, and doing a sweep. Dodge this initial attack because it packs a punch.
Spear Combo
Three sequential spear swings, dodge through them, then immediately counter with an ability when the third swing ends.
Shockwave

She rises high, swoops in for 2 slams, and a vertical beam appears below her. The beam will pulse bright blue right before she drops. That's your cue. Jump the moment you see that pulse to get clear of the shockwave. This one is easy to miss the first time since the visual cue is different from everything else in the fight.
Arrow rain
She ascends and floods the arena with arrows. Red circles with different sizes and explosion timing mark impact zones. Keep moving constantly and don't stop to attack until the barrage ends.
Interrupt Her Attacks
Interrupt her charged skills whenever you spot the opening, and keep chipping away at her stagger bar between combos. Once you hit each stagger checkpoint, that's when you go all in and unleash your most powerful attacks.
Tata's Sacrifice

Take Marble Aggelomoirai's HP to zero, and witness Tata's heroic sacrifice to complete Undying Cinders. The path to what comes next opens up, and Process 4 starts moving toward its conclusion.
| Previous / Next Story | |
|---|---|
| Frontline Rush | Temporary Peace |
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