Chromatius, Dragonspawn: how to beat

Chromatius, Dragonspawn — dungeon “Lower Spire of Cindermount”, level 52. The deck: phases, turn cycle, damage and healing by mode, cold, test strike, role…

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Dungeon Lower Spire of Cindermount, boss 4 of 7, level 52.

The boss plays its own deck: every turn it plays the next line of its phase’s cycle, with no randomness. Learn the cycle and you know what is coming. The numbers on this page are the same as in the card tooltip in combat: before Hardiness and Defender’s Stance. Mechanics in detail — Boss mechanics.

In short

Modes: Heroic (at level 60), Normal (at the place’s level, 48–57), Keystone +10 (Mythic+, at level 60).
2 phases, 7 cards in the deck. Schools: ☠ Poison 4, 🩸 Blood 1, 🌿 Nature 1, ⚔ Physical 1.
“Cold Blood” cold: every enemy turn, everyone through shields — heroic 1,160, keystone +10 960 to each before Hardiness. No cold in normal mode.
“Stinger Under the Ribs” test strike — on boss turns 8 and 16: heroic 7,000, keystone +10 8,000; 40% weaker with a defensive card on yourself.
The heaviest hit is “Stinger Under the Ribs”: heroic 7,000, keystone +10 8,000.

Phases and turn cycle

The phase changes with the boss’s Health. In each phase the boss goes round its own cycle: at the end it starts again. The boss’s next turn shows on its portrait.

1. “Weaving” — from the start of the fight

Down to 50% Health.

Cycle step	What the boss plays
1	☠ Crossbreed Bite
2	☠ Crossbreed Bite + ☠ Venomous Spit
3	🌿 Masonry
4	☠ Crossbreed Bite + ☠ Venomous Spit
5	⚔ Shedding Skin

2. “Second Clutch” — below 50% Health

Below 50%: a clutch at once, angrier.

On entering the phase the boss plays at once: 🩸 Second Clutch, 🌿 Masonry.

Cycle step	What the boss plays
1	☠ Crossbreed Bite + ☠ Venomous Spit
2	☠ Crossbreed Bite
3	🌿 Masonry + ☠ Venomous Spit
4	⚔ Shedding Skin

The “Stinger Under the Ribs” test strike is not part of the cycle: the boss announces it on its turns 7 and 15 and hits on turns 8 and 16.

Cards and numbers

The number is what a hit takes before Hardiness (through shields — from Health only), how much the boss heals itself, the shield it puts up, a minion’s Health. A dash means the card is not in that mode or has no number. Keystone: +10 numbers; hits are the same from +7 to +9 and weaker per level below +7.

Card	What it does	Heroic	Normal	Keystone +10	How to answer
☠ Stinger Under the Ribs · Poison, test strike	A test strike on whoever holds the boss’s attention (usually the tank). The boss announces it on its own, outside the cycle, and hits on its 8th and 16th turn; one turn before, there is a countdown on the portrait and a warning above your hand. The target plays a defensive card on themselves before the hit — it is 40% weaker. Not in normal mode. Through shields.	7,000 · with a defensive card 4,200	—	8,000 · with a defensive card 4,800	Test strike, one turn of warning. The tank plays a defensive card, the healer tops him up in advance.
☠ Crossbreed Bite · Poison, hit	A hit on whoever holds the boss’s attention (usually the tank).	2,300	650	4,100	A plain hit.
☠ Venomous Spit · Poison, stacking damage over time	Damage over time on everyone that stacks: each play adds a stack, up to 5. The number is per turn per stack; a stack lasts 5 turns.	104 per turn per stack	20 per turn per stack	123 per turn per stack	On everyone, builds up, wears off by itself. Party healing; a cleanse, if you have one, makes it easier.
🌿 Masonry · Nature, summon with a task	Summons “Crossbreed Egg” ×2. If it survives 2 turns it explodes: “Hatched”.	Health 680	Health 220	Health 2,720	Two eggs. Smash them within 2 turns or they hatch and bite everyone.
☠ Hatched · Poison, hit on everyone	A hit on everyone: the number is for each. Shields hold half.	518	98	615	If the eggs were not smashed. Half through shields at everyone.
⚔ Shedding Skin · Physical, opening: more damage to the boss	The boss is open: damage to it ×1.3 for 2 turns.	—	—	—	+30% damage for 1 party turn.
🩸 Second Clutch · Blood, boss empower	The boss’s hits ×1.15 until the fight ends.	—	—	—	Stronger by 15% until the fight ends.

“Cold Blood” cold

Half spider. Spiders do not warm up.

Heroic: 1,160 to each per enemy turn, before Hardiness.
Keystone +10: 960 to each per enemy turn, before Hardiness.
Hits every fighter in the party through shields; Hardiness reduces it — better gear takes less.
The answer is healing every turn: shields do not stop cold. Healer cards do it best — they heal Health only.
No cold in normal mode.

Test strike

“Stinger Under the Ribs” — on boss turns 8 and 16, through shields, on whoever holds the boss’s attention (usually the tank). On heroic, while the party’s tank is alive, it goes to the tank. Not in normal mode.
Heroic: 7,000 before Hardiness; 4,200 if the target answered with a defensive card.
Keystone +10: 8,000 before Hardiness; 4,800 if the target answered with a defensive card.
One turn before the hit there is a countdown on the portrait and a warning above your hand. The target plays a defensive card on themselves: a self-shield, damage reduction or “cannot be killed”. A card someone else plays on the target does not count.

Enrage

Heroic: from party turn 40, every boss turn is 4% stronger, and it stacks.
Normal: as before — if the fight drags on past its expected length, the boss hits harder every turn.
Keystone +10: as before — if the fight drags on past its expected length, the boss hits harder every turn.

Roles

Tank

The “Stinger Under the Ribs” test strike lands on the boss’s 8th and 16th turn (heroic and keystone +10). One turn before, play a defensive card on yourself — a self-shield, damage reduction or “cannot be killed”: the hit becomes 40% weaker. Keep such a card in hand for those turns.
Shields do not stop this hit: the healer tops up your Health before it.
“Crossbreed Bite” hits you. Keep Taunt on rhythm: while the boss hits the tank, the rest stay whole. The heaviest is “Crossbreed Bite” (“Weaving” phase, cycle step 1).
Do not fall: on heroic, mythic and in keystones, without a living tank the boss’s hits on its focus go through shields. A resident can be the tank too.

Healer

“Cold Blood” cold hits everyone through shields every enemy turn: heroic — 1,160, keystone +10 — 960 to each before Hardiness. Heal everyone every turn; healer cards do it best — they heal Health only.
“Hatched” and “Venomous Spit” hit everyone. Before such turns, get everyone above half Health; “Hatched” goes half through shields: shields hold half, the rest hits Health.
“Venomous Spit”: damage over time — outheal it; a cleanse helps.
“Second Clutch”: the boss hits harder — keep crystals and heals in reserve for those turns.

Damage dealers

“Crossbreed Egg” explodes if it survives 2 turns — kill it before then.
“Shedding Skin”: the boss is open and takes more damage — save your strong cards for that turn.
Do not drag it out: heroic — enrage from turn 40.

The heaviest hits

“Stinger Under the Ribs” — test strike, through shields.
“Crossbreed Bite” — on the tank; “Weaving” phase, cycle step 1.
“Hatched” — on everyone, half through shields.

Loot

All of the boss’s loot with rough drop chances is in the item atlas; rules and items by boss are on the Lower Spire of Cindermount page.

Previous boss — Bonegnawer, the Carrion Feeder. Next boss — Cindereater, Minion of Fire.

All bosses of the place — Lower Spire of Cindermount. Rules of a fight against a boss with a deck — How to beat: every boss.