The Crimson Warden
Boss · The Phlegethon · band C, The Nine Circles

Where The Crimson Warden waits
The Crimson Warden holds the gates at depths 17,600, 17,900, 18,200, 18,500, 18,800, 19,100 and onward in The Phlegethon, sharing the zone's 100-depth gate rhythm with The Boiling Tyrant and The Flayed Colossus.
What The Crimson Warden is
The Crimson Warden is a Knight: it swings a sword, and the body asks for fast builds beware: the more you swing, the more it hits back — and it wards off blows from afar. As a boss it wears the type's defences at 35%, carries no status of its own, and enrages below half health: it hits harder and moves faster.
The Crimson Warden by the numbers
The card at each gate — health, damage per swing, armour and the modifiers it rolls — straight from the game's spawn table. On the floor the boss leads with 60% of the card's health and 60% of its damage, before the road's own pressure.
What those modifiers do
BURNING- +35% ignite chance; a quarter of its physical damage becomes fire
ARMORED- Armour ×1.9, at the cost of 5% of its health
DENSE- takes 60% less from damage over TIME, and double from hits
ROTPROOF- +75% chaos resistance (capped at 75%)
OF CHILLING DEATH- leaves a pool of frost where it falls
MANGLING- +35% chance to cause bleeding
PIERCING- penetrates 25% of your resistances
FIREPROOF- +75% fire resistance (capped at 75%)
VENOMOUS- +35% chance to poison you
SHOCKING- +35% shock chance; a quarter of its physical damage becomes lightning
OF POWER- gains a Power charge on every hit it lands: +200% critical chance each, up to 3
FROSTBOUND- +75% cold resistance (capped at 75%)
REGENERATING- Heals 1% of its maximum health every second
CORRUPTING- a third of its damage is chaos
THICK-SKINNED- Overwhelm and armor you ignore count at half
OF FLAMING DEATH- leaves a pool of fire where it falls
DEADLY- +20% critical strike chance
OF DAMAGING- the pack within 4.5 tiles hits 25% harder
Modifiers are rolled per depth and are the same for every player. Bosses always carry at least 3 and never a pace modifier (SWIFT, BRUTE), so a boss's swing rhythm is its own; of the seals only the walls — BLOODLESS, INERT, ASHEN, ETHEREAL, DENSE — ride a boss. The full list is in Enemy modifiers.
At its first gate The Crimson Warden leads with 3,651,234,271 health, against 3,757,551,703 for the leader one floor above, and swings every 1.25s.
What a gate floor is
A gate is a floor like any other, with the boss leading its last pack. Nothing below it opens until the floor is cleared. A lost floor costs nothing; you can fight it again. How a floor is fought is under Combat.
Fight The Crimson Warden — play free