JuiblexHuge fiend (demon)
Foul. Any creature, other than an ooze, that starts its turn within 2 meters of Juiblex must succeed on a DC 21 Fortitude saving throw or be poisoned until the start of the creature’s next turn.
Legendary Resistance (3/day). If Juiblex fails a saving throw, it can choose to succeed instead.
Magic Resistance. Juiblex has advantage on saving throws against spells and other magical effects.
Magic Weapons. Juiblex’s weapon attacks are magical.
Regeneration. Juiblex regains 20 health at the start of its turn. While the juiblex is able to regenerate, it does not become wounded or incapacitated as a result of regaining health. If it takes fire or radiant damage, this trait doesn’t function at the start of its next turn. Juiblex dies only if it starts its turn with 0 health and doesn’t regenerate.
Spellcasting. The juiblex uses Divinity (Cha) to cast spells (spell save DC 20, +12 to hit with spell attacks). It has 22 mana, a mana limit of 4, regains all expended mana when it finishes a long rest and regains half its total mana when it finishes a short rest. It knows the following spells:
At will: detect magic
Cantrips (at will, 29th-level spellcaster): corrode
1 mana: blight
2 mana: gaseous form
3 mana: contagion
Spider Climb. Juiblex can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Acid Lash. Melee Weapon Attack: +14 to hit, reach 2 m. Hit: 21 (4d6 + 7) acid damage. Any creature killed by this attack is drawn into Juiblex’s body, and the corpse is obliterated after 1 minute.
Eject Slime (Recharge 5–6). Juiblex spews out a corrosive slime, targeting one creature that it can see within 10 meters of it. The target must make a DC 21 Reflex saving throw. On a failure, the target takes 55 (10d10) acid damage. Unless the target avoids taking any of this damage, any metal armor worn by the target takes a permanent −1 penalty to the Defense it offers, and any metal weapon it is carrying or wearing takes a permanent −1 penalty to damage rolls. The penalty worsens each time a target is subjected to this effect. If the penalty on an object drops to −5, the object is destroyed.
Legendary Actions (3)
Only one legendary option can be used at a time and only at the end of another creature’s turn. The juiblex regains spent legendary actions at the start of its turn.
Acid Splash. Juiblex casts acid splash.
Attack. Juiblex makes one acid lash attack.
Corrupting Touch. Melee Weapon Attack: +14 to hit, reach 2 m. Hit: 21 (4d6 + 7) poison damage.
On initiative count 20 (losing initiative ties), the juiblex takes a lair action to cause one of the following effects; the same effect can’t be used two rounds in a row:
Juiblex slimes a square area of ground it can see within the lair. The area can be up to 2 meters on a side. The slime lasts for 1 hour or until it is burned away with fire. When the slime appears, each creature in that area must succeed on a DC 21 Reflex saving throw or become restrained. When a creature enters the area for the first time on a turn or ends its turn there, that creature must make the same save. A restrained creature is stuck as long as it remains in the slimy area or until it breaks free. The restrained creature, or another creature who can reach it, can use an action to try to break free and must succeed on a DC 21 Brawn check. If the slime is set on fire, it burns away after 1 round. Any creature that starts its turn in the burning slime takes 22 (4d10) fire damage.
Juiblex slimes a square area of ground it can see within the lair. The area can be up to 2 meters on a side. The slime lasts for 1 hour or until it is burned away with fire. When the slime appears, each creature on it must succeed on a DC 21 Reflex saving throw or fall prone and slide 2 meters in a random direction determined by a d8 roll. When a creature enters the area for the first time on a turn or ends its turn there, that creature must make the same save. If the slime is set on fire, it burns away after 1 round. Any creature that starts its turn in the burning slime takes 22 (4d10) fire damage.
A green slime (see the Dungeon Master’s Guide) appears on a spot on the ceiling that Juiblex chooses within the lair. The slime disintegrates after 1 hour.
The region containing the juiblex's lair is warped by the juiblex’s magic, which creates one or more of the following effects:
Small bodies of water, such as ponds or wells, within 2 kilometers of the lair turn highly acidic, corroding any object that touches them. Surfaces within 10 kilometers of the lair are frequently covered by a thin film of slime, which is slick and sticks to anything that touches it.
If a humanoid spends at least 1 hour within 2 kilometers of the lair, that creature must succeed on a DC 20 Will saving throw or descend into a madness determined by the Madness of Juiblex table. A creature that succeeds on this saving throw can’t be affected by this regional effect again for 24 hours.
If Juiblex dies, these effects fade over the course of 1d10 days.
No concoctions, maneuvers, or spells
All creatures in this system should have maneuvers or spells. You should add some maneuvers or spells to this creature. If you do so, please make a suggestion on github so I can finish adding maneuvers and spells to all creatures via https://github.com/mlenser/kryx-rpg-issues/issues/9