The Marrow Colossus
Boss · The Well of Giants · band D, The Foundations

Where The Marrow Colossus waits
The Marrow Colossus holds the gates at depths 32,600, 33,200, 33,800, 34,400, 35,000 in The Well of Giants, sharing the zone's 100-depth gate rhythm with Ephialtes the Chained and Nimrod the Babbler and Antaeus Unbound and The Foundation Stone and Warden of the Well.
What The Marrow Colossus is
The Marrow Colossus is a Brute: it swings a mace, and the body asks for the guard shell, armor against a heavy blow, stalling — it wards off blows from afar and hooks you in. 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 Marrow Colossus 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
WITHERING- every blow leaves damage over time on you: 15% of the blow each second for 4 s
DRAINING- you recover half as much: leech, regen, recoup
FROSTBOUND- +75% cold resistance (capped at 75%)
DENSE- takes 60% less from damage over TIME, and double from hits
ENRAGED- builds 2 Rage with every blow it lands, up to 50; each point is 1% more damage
BARRIERED- Opens behind a barrier worth 25% of its health
REGENERATING- Heals 1% of its maximum health every second
OF FRENZY- gains a Frenzy charge on every hit it lands: 4% more damage, +15% attack speed and +5% movement each, up to 3
SUNDERING- every blow cuts your armor by 30% for 4 s
OF DAMAGING- the pack within 4.5 tiles hits 25% harder
SHOCKING- +35% shock chance; a quarter of its physical damage becomes lightning
STORMSHIELDED- +75% lightning resistance (capped at 75%)
OVERWHELMING- ignores 30 points of your armor
CHILLING- Turns 30% of its physical damage into cold
ROTPROOF- +75% chaos resistance (capped at 75%)
OF CHILLING DEATH- leaves a pool of frost where it falls
EVASIVE- +22% chance to dodge your hits
EXPOSING- every blow cuts your resistances by 15 for 4 s
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 Marrow Colossus leads with 13,825,663,448 health, against 11,059,826,734 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 Marrow Colossus — play free