Karthus, the Deathsinger
Medium undead, Chaotic Neutral
- Armor Class 14
- Hit Points 36 (8d8+0)
- Speed 30
STR DEX CON INT WIS CHA 5 (-3) 5 (-3) 10 (+0) 18 (+4) 16 (+3) 16 (+3)
- Saving Throws CON +5, INT +9
- Skills Arcana +9, Medicine +9, Performance +8
- Damage Vulnerabilities Fire
- Damage Resistances Force, Nonmagical, Psychic
- Damage Immunities Necrotic, Poison
- Condition Immunities Poisoned, Turn undead
- Senses Blindsense 120ft, True Sight 30ft
- Languages Common
- Challenge 8 (3,900xp)
Against the Living. Karthus' abilities can only ever affect living creatures unless otherwise stated.
Death Defied. When Karthus drops to zero hit points, his physical form disintegrates and disappears from view. A haunting cadence forms and quickly rises in volume to a great crescendo as he uses Requiem. At the start of the next round, Karthus reforms as an incorporeal specter, rolling initiative and acting as though it was the first round of combat.
Karthus reforms with half of his hit points and Death Defied cannot be used for another 24 hours. Once defeated in his incorporeal form, he returns to his lair, reforming within his phylactery after 1d6 years.
In incorporeal form, Karthus can only take damage from spells and magical weapons.
Funeral Dirge. - When Karthus kills a creature, it rises as a zombie under his control.
Actions
Lay Waste. Karthus chooses a 4x4 space on grid that he can see, creating a 5ft radius sphere of destructive necrotic energy.
Any creature within the radius must succeed on a DC 16 dexterity saving throw to leave the area, as agonised spirits of the damned claw at the flesh to hold them in their dark embrace. At the start of the next round, the sphere detonates, dealing necrotic damage to creatures inside, based on the number of creatures present.
When the sphere detonates, if there is only one creature inside, it takes 4d6 necrotic damage. If there are two creatures inside, they each take 2d6 necrotic damage. If there are three or more creatures inside, they each take 1d6 necrotic damage.
A creature can try to extract another creature by succeeding on a shove attack against them, moving them 5 feet in any direction on a success.
Wall of Pain. Karthus creates a 5ft wide by 30ft long veil of ghostly energy that lasts for two rounds, ending at the start of his turn. Any creature that passes through the veil has their movement reduced by half. At the start of an affected creatures' turn, its movement increases by 5 feet until their normal movement speed has been restored, at which point its movement ceases increasing.
Additionally, when an affected creature takes necrotic damage, it suffers twice the amount of damage dice until its movement speed is restored to normal. Magical effects that increase the movement of a creature can prematurely end this increase in damage.
As a reaction at the start of the first round of combat, Karthus can use this ability.
Defile (4-6). Karthus summons a ring of deathly energy around himself, extending 15 feet from his position. Any creature within the ring must succeed on a constitution saving throw against a DC of 16 or take 8d6 necrotic damage, taking half that amount on a success.
If a creature is reduced to zero hit points or killed by Defile, Karthus uses his Lay Waste ability, or detonates an existing one. Additionally, reducing a creature to zero hit points with Defile also restores hit points to the damage dealt to all undead creatures under Karthus' control, split between each of them.
Requiem. At the start of the round that Karthus reforms through the use of Death Defied, any creature of Karthus' choosing that took part in the fight that triggered Death Defied takes 12d6 necrotic damage. If a creature is dropped to zero hit points, they immediately suffer two failed death saving throws.
Every medium or smaller beast, plant creature and plant within one mile is instantly killed. Any existing dead creature rises as a skeleton or zombie based on how long it had been dead under Karthus' control.