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From Pathfinder #221: Into the Apocalypse Archive, which isn't enabled.

Lythazossa

CREATURE 20
UNIQUEGARGANTUANGHOSTINCORPOREALMYTHICSPIRITUNDEADUNHOLY

Variant cairn linnorm ghost

Perception +35; darkvision, scent (imprecise) 60 feet, truesight 60 feet
Languages Aklo, Draconic, Fey, Thassilonian
Skills Acrobatics +36, Athletics +35, Intimidation +37, Stealth +38
Str -5, Dex +8, Con +0, Int -2, Wis +7, Cha +9
Remove a Condition (concentrate)
Cost 1 Mythic Point
Effect Lythazossa ends one condition affecting her.
Constant Spells

A constant spell affects the monster without the monster needing to cast it, and its duration is unlimited. If a constant spell gets counteracted, the monster can reactivate it by spending the normal spellcasting actions the spell requires.

AC 44; Fort +28, Ref +36, Will +33; +1 status to all saves vs. magic
HP 280, rejuvenation, void healing; Immunities acid, curse, paralyzed, bleed, death effects, disease, poison, precision, sleep, unconscious; Resistances all damage 15 (except force, ghost touch, spirit, or vitality; double resistance vs. non-magical), mythic 20
+1 Status to All Saves vs. Magic
Mythic Resilience (Reflex)

The creature treats its saving throws with the associated save as one degree of success better than it rolled. This is not cumulative with other effects that change their degree of success, like the incapacitation trait (except for rolling a natural 1 or 20). Each time the monster gains mythic resilience, choose one save. The ability should apply to the creature's highest saves first.

Reactive Strike (Spectral Tail Only)

Trigger A creature within the monster's reach uses a manipulate action or a move action, makes a ranged attack, or leaves a square during a move action it's using.
Effect The monster attempts a melee Strike against the triggering creature. If the attack is a critical hit and the trigger was a manipulate action, the monster disrupts that action. This Strike doesn't count toward the monster's multiple attack penalty, and its multiple attack penalty doesn't apply to this Strike.

Rejuvenation (divine)

When Lythazossa is destroyed, she re-forms after 2d4 days in the Prosperity Vault, fully healed. She can be permanently destroyed if the apocalypse seed is removed from Varisia.

Undying Myth
Cost all of Lythazossa's Mythic Points
Trigger Lythazossa would be destroyed and has at least 1 Mythic Point
Effect Lythazossa remains active, and recovers 140 healing Hit Points.
Void Healing

A creature with void healing draws health from void energy rather than vitality energy. It is damaged by vitality damage and is not healed by vitality healing effects. It does not take void damage, and it is healed by void effects that heal undead.

Speed fly 100 feet; unfettered movement
Melee Spectral Jaws +38 (finesse, magical, reach 25), Damage 4d12+10 void plus Vestige Of An Ancient Curse
Melee Spectral Claw +38 (agile, finesse, magical, reach 25), Damage 4d8+10 void
Melee Spectral Tail +38 (agile, finesse, magical, reach 25), Damage 4d10+10 void
Primal Innate Spells DC 42, attack +34; Constant (9th) Truesight, Unfettered Movement
Calamitous Roar (auditory, divine, emotion, fear, mental)

Lythazossa laments her cursed fate. Each living creature within 30 feet attempts a DC 42 Will save with the following results.

Critical Success The creature is unaffected and is temporarily immune to Calamitous Roar for 1 minute.

Success The creature is unaffected.

Failure The creature becomes Frightened 2

Critical Failure The creature becomes Frightened 3

Recharge (concentrate)
Cost 1 Mythic Point
Effect Lythazossa can use Soul-Melting Breath again.
Reroll (fortune)
Cost 1 Mythic Point
Trigger Lythazossa fails a check
Effect Lythazossa rerolls the check.
Soul-Melting Breath (acid, divine)

Lythazossa expels a 60-foot cone of ghostly acid that melts a creature's very soul, dealing 20d6 spirit damage to creatures in the area (DC 42 basic Will save). The ghostly acid also saps the life from affected creatures. At the beginning of Lythazossa's next turn, each creature that failed the Reflex save must succeed at a DC 42 Fortitude save or become Drained 1 (Drained 2 on a critical failure). Lythazossa can't use Soul-Melting Breath again for 1d4 rounds.

Telekinetic Assault (divine)

Lythazossa cries out in pain and anguish, hurling small objects and debris is a 30-foot emanation. Creatures in the area take 10d6 bludgeoning damage (DC 42 basic Reflex save).

Vestige of an Ancient Curse (curse, primal)

When Lythazossa hits a creature with her jaws Strike, the target must succeed at a DC 42 Will save or become Enfeebled 2 until Lythazossa's spirit is put to rest. If the target critically fails this saving throw, Lythazossa regains 40 healing HP, and the target is instead Enfeebled 3.

Pathfinder #221: Into the Apocalypse ArchiveORC