It broke the vault floor into three. Two of them are always burning.
Bosses
Breaker of the Floor
It broke the vault floor into three. Two of them have burned ever since.
Magma SlamSlag SpitMolten MaulThe Sundering FloorSunderingCinder Orbs
The Deep Burns at 50% health: The lava moves more often with less warning, and more Cinder Orbs fall.
Loot
Personal loot, item level 20. Full spoils once per boss per character per day.
WarriorEvery kill: one of these, guaranteed (a second at 35%)
Magmaforged Axe+82 Health, +14% Armor, +7% Power
Magmaforged Kite Shield+5% Armor, +4% Dodge, +10% Power
Sundered Legplates+8% Armor, +6% Dodge
Magmaforged Sabatons+59 Health, +5% Armor, +10% Power
Sundered Loop+7% Armor, +7% Power
Magmaforged Warbelt+118 Health, +5% Armor, +4% DodgeRaid set and legendary
Vaultbreaker Warhelm+106 Health, +11% Armor20% per kill+10% each miss
The Sundered Ember+122 Health, +13% Armor2% per kill+1% each miss
Recipe: Heartforged LegplatesTeaches you to make Heartforged Legplates.15% per killRepeat kills the same day one Gilded Chest roll from this list
RogueEvery kill: one of these, guaranteed (a second at 35%)
Sundered Fangs+11% Dodge, +6% Critical, +7% Power
Magmaforged Breeches+8% Dodge, +4% Critical, +5% Power
Deepfire Treads+6% Critical, +8% Power
Magmaforged Band+53 Health, +7% Critical, +5% Power
Deepfire Belt+89 Health, +6% CriticalRaid set and legendary
Rivenshade Hood+7% Dodge, +9% Critical20% per kill+10% each missThe Sundered Ember+8% Dodge, +10% Critical2% per kill+1% each miss
Recipe: Cinderhide LeggingsTeaches you to make Cinderhide Leggings.15% per killRepeat kills the same day one Gilded Chest roll from this list
WizardEvery kill: one of these, guaranteed (a second at 35%)
Magmaforged Spire+11% Critical, +7% Power, +17% Regen
Sundered Tome+8% Critical, +5% Power, +12% RegenMagmaforged Leggings+6% Critical, +8% PowerMagmaforged Striders+59 Health, +8% Critical, +5% Power
Sundered Ring+7% Power, +16% Regen
Deepfire Cord+8% Critical, +5% Power, +12% RegenRaid set and legendary
Lodestar Crown+12% Power, +19% Regen20% per kill+10% each missThe Sundered Ember+14% Power, +22% Regen2% per kill+1% each miss
Recipe: Hymnweave TrousersTeaches you to make Hymnweave Trousers.15% per killRepeat kills the same day one Gilded Chest roll from this list
PriestEvery kill: one of these, guaranteed (a second at 35%)
Sundered Mace+6% Critical, +7% Power, +33% Regen
Sundered Censer+59 Health, +10% Power, +12% RegenMagmaforged Trousers+89 Health, +8% PowerMagmaforged Sandals+118 Health, +5% Power, +12% Regen
Deepfire Band+6% Critical, +16% RegenDeepfire Cord+60 Health, +10% Power, +12% RegenRaid set and legendary
Crownlight Diadem+11% Power, +21% Regen20% per kill+10% each missThe Sundered Ember+13% Power, +25% Regen2% per kill+1% each miss
Recipe: Signet of the Unbroken HymnTeaches you to make Signet of the Unbroken Hymn.15% per killRepeat kills the same day one Gilded Chest roll from this list
DruidEvery kill: one of these, guaranteed (a second at 35%)
Deepfire Staff+7% Armor, +7% Power, +33% Regen
Magmaforged Seed Pouch+59 Health, +4% Critical, +10% PowerDeepfire Leggings+8% Power, +18% RegenDeepfire Treads+59 Health, +5% Armor, +10% Power
Deepfire Band+7% Power, +16% RegenDeepfire Sash+59 Health, +4% Critical, +24% RegenRaid set and legendary
Magmaroot Antlers+106 Health, +11% Power20% per kill+10% each missThe Sundered Ember+122 Health, +13% Power2% per kill+1% each miss
Recipe: Flask of the ForgeheartTeaches you to make Flask of the Forgeheart.15% per killRepeat kills the same day one Gilded Chest roll from this list
Materials and more
20 Warden's Marks2 × boss gold
Ember Shard 100%
Ashbloom 70%
Minor Healing Draught 50%
Bog Hide 35%
Slimy Root 25%Bog Moss 25%Recipe for your profession 12%
Greater Rune of Precision 3.1%
Greater Rune of Might 3.1%
Greater Rune of Vigor 3%
Greater Rune of Wind 3%
Greater Rune of Tides 3%
Greater Rune of Stone 2.9%
Greater Rune of Swiftness 2.9%
Runecarver's Chisel 2%
Rune of Vigor 1.4%
Rune of Stone 1.3%
Rune of Wind 1.3%
Rune of Swiftness 1.3%
Rune of Precision 1.3%
Rune of Might 1.2%
Rune of Tides 1.2%Guide
The beast that broke the vault floor. The arena is split into three sectors, and two of them are always lava.
Deadly The Sundering Floor: The arena is three sectors, left, middle and right. Lava covers every sector but one. Lava takes 24% of a hero's health every half second.
Sundering: Every 21 seconds the lava moves one sector over. The warning lasts 6 seconds: the lava drains from the next sector at once, and floods the current one when the warning ends.
Deadly Cinder Orbs: After every shift, three orbs land in the safe sector and burst 8 seconds later. One hero in an orb takes 50% of their health and is Scorched for 10 seconds. An orb with nobody in it hits everyone for 50%. Two or more heroes in one orb are all struck down, and so is a Scorched hero who takes another.
Magma Slam: A 110 degree cone in front of Kaldrak fills and bursts for heavy damage.
Slag Spit: Two circles land around the heroes and leave burning ground.
Molten Maul: Its melee swing adds a Brand stack for 12 seconds (12% more damage from Kaldrak per stack, up to 8).
The Deep Burns Below 50%: The lava moves every 16 seconds with a 4.5 second warning, and four orbs fall, bursting after 7 seconds.
Enrage: After 5 minutes Kaldrak hits twice as hard and much faster.