I used the adventure “Spire of Quetzal” as the exit from the Gardens of Ynn. My PCs did what they could to avoid combat with Quetzal and after she possessed a character, knocked that character out before fleeing back to their homeward – The Ninth World. Here are her 5e stats. I changed Quetzal to be a sidh who used undeath to avoid the Idea of Thorns.
Quetzal, The Sidh Sorcerer-Queen
Medium undead, lawful evil
AC 17, HP 143, Speed 30 ft.
STR +4, CON +8, INT +5, WIS +9, CHA +8
Damage Vulnerabilities Fire
Damage Immunities Necrotic, Poison; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks
Senses Darkvision 60 ft., Passive Perception 14
Languages Sidh CR 15 (13,000 XP), Proficiency Bonus +5
Spellcasting. Quetzal is a 10th-level spellcaster. Her spellcasting ability is Wisdom (spell save DC 17, +9 to hit with spell attacks). Quetzal has the following cleric spells prepared:
- Cantrips (at will): sacred flame, thaumaturgy
- 1st level (4 slots): command, guiding bolt, shield of faith
- 2nd level (3 slots): hold person, silence, spiritual weapon
- 3rd level (3 slots): animate dead, dispel magic
- 4th level (3 slots): divination, guardian of faith
- 5th level (2 slots): contagion, insect plague
- 6th level (1 slot): harm
Magic Resistance. Quetzal has advantage on saving throws against spells and other magical effects.
Rejuvenation. If Quetzal is destroyed, she gains a new body in 24 hours if her Black Gem heart is intact, regaining all her hit points and becoming active again. The new body appears within 5 feet of her heart.
Protected Against Projectiles. Any solid projectile fired at Quetzel turns into a bird in mid-flight, loops around her, flies back at the shooter and then transforms back into the projectile at the last moment. All projectile attacks miss Quetzel and hit the attacker instead.
Black Gem Possession. Anyone touching the black gem is instantly possessed by Quetzel. The ghost then disappears, and the target is incapacitated and loses control of its body. The ghost now controls the body but doesn’t deprive the target of awareness. Quetzel can’t be targeted by any attack, spell, or other effect, except ones that turn undead, and it retains its alignment, Intelligence, Wisdom, Charisma, and immunity to being charmed and frightened. It otherwise uses the possessed target’s statistics, but doesn’t gain access to the target’s knowledge, class features, or proficiencies.
The possession lasts until the body drops to 0 hit points, the Quetzel ends it as a bonus action, or the ghost is turned or forced out by an effect like the dispel evil and good spell. When the possession ends, Quetzel immediately returns to her mummy body. The target is immune to this ghost’s Possession for 24 hours after succeeding on the saving throw or after the possession ends. Female characters are particularly susceptible to this possession and must make a WIS saving throw to resist touching the gem. Quetzel will use this secondary effect on the highest CHA female in order from highest to lowest until she succeeds at possessing the target.
Multiattack. Quetzal can use one of her Monster Attack options on her turn (roll randomly or go through the list) as well as cast a spell or use rotting fist.
- Rotting Fist.Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 3d6 + 4 bludgeoning damage plus 6d6 necrotic If the target is a creature, it must succeed on a CON saving throw or be cursed with mummy rot. The cursed target can’t regain hit points, and its hit point maximum decreases by 3d6 for every 24 hours that elapse. If the curse reduces the target’s hit point maximum to 0, the target dies, and its body turns to dust. The curse lasts until removed by the remove curse spell or other magic.
- The Longsword Nariska.Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 3d6 + 4 slashing damage plus 6d6 necrotic If the target is a creature, it must succeed on a CHA saving throw or be filled with self-loathing as the target losses 1d4 CHA and/or WIS ability score every time they take a rest (long or short). If the curse reduces the target’s CHA and WIS to 0 they commit suicide. The curse lasts until removed by the remove curse spell or other magic.
- Demonic Double. Quetzel summons a demonic doppelganger from the shadow of an adventurer. This creature looks exactly like the victim and has the same stats but is utterly evil and can never tell the truth. It will try to kill them and take over their life. It does not disappear when Quetzel dies. It must be independently destroyed. Photocopy the cursed PC’s character sheet and the double falls under the DM’s control. The double will look identical to the original except there will be one change – for example all black clothes, a devilish goatee etc.
- Gravity Switch. Quetzal casts reverse gravity.
- Blasting Scream! Quetzel screams. The nebulae beyond the dome boil. All adventurers within 30 feet must make a WIS saving throw with disadvantage or be blasted out of their bodies for one round, losing the ability to act. If multiple people are so affected, they will return to random bodies.
- Iridescent Mutating Fire! Quetzel hurls a powerful magical bolt of green fire which inflicts 6d6 points of radiant damage or mutates a random body part into a birdlike form. The victim may choose whether to take the damage or the mutation. The mutations do not disappear with the death of Quetzel.
- WRATH OF NARSIKA! The Demon-Queen lets the sword Narsika sing and performs a lighting quick slashing attack against two adventurers. Take the Narsika attack action. an attack at each with ten Base Dice and one D10 Artifact Die, Weapon Damage 2 (slash wound).
- The Horrible Gaze of the Abyss.Quetzal targets one creature she can see within 60 feet of her. If the target can see her, it must succeed on a WIS saving throw against this magic or become frightened until the end of her next turn. If the target fails the saving throw by 5 or more, it is also paralyzed for the same duration. A target that succeeds on the saving throw is immune to the Dreadful Glare of Quetzal, all mummies and mummy lords for the next 24 hours.
Quetzal can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. Quetzal regains spent legendary actions at the start of its turn.
- Monster Attack.Quetzal makes one attack with her rotting fist or uses the next option in the Monster Attack table.
- Blinding Dust.Blinding dust and sand swirls magically around the Quetzal. Each creature within 5 feet of the mummy lord must succeed on a CON saving throw or be blinded until the end of the creature’s next turn.
- Blasphemous Word (Costs 2 Actions).Quetzal utters a blasphemous word. Each non-undead creature within 10 feet of her that can hear the magical utterance must succeed on a DC 16 Constitution saving throw or be stunned until the end of Quetzal’s next turn.
- Channel Negative Energy (Costs 2 Actions).Quetzal magically unleashes negative energy. Creatures within 60 feet of her, including ones behind barriers and around corners, can’t regain hit points until the end of the Quetzal’s next turn.
- Whirlwind of Birds (Costs 2 Actions).Quetzal magically transforms into a whirlwind of colourful birds, moves up to 60 feet, and reverts to her normal form. While in whirlwind form, she is immune to all damage, and it can’t be grappled, petrified, knocked prone, restrained, or stunned. Equipment worn or carried by Quetzal remain in her possession.
On initiative count 20 (losing initiative ties), the mummy lord takes a lair action to cause one of the following effects; the mummy lord can’t use the same effect two rounds in a row.
- A Trap Treasure Triggers. See the adventure for details.
- Until initiative count 20 on the next round, any non-undead creature that tries to cast a spell of 4th level or lower in the mummy lord’s lair is wracked with pain. The creature can choose another action, but if it tries to cast the spell, it must make a CON saving throw. On a failed save, it takes 1d6 necrotic damage per level of the spell, and the spell has no effect and is wasted.