Here is an updated Pudding King for Out of the Abyss. My players never made it this far as they were killed by the myconid fungal zombie horde in Neverlight Grove. Should be a challenge to level 5 to 6 characters especially after they had run the gauntlet of slimes and oozes protecting him in Out of the Abyss.
THE PUDDING KING
Small humanoid (gnome, shapechanger), chaotic evil
Armour Class 16 (mage armour plus blur) Hit Points 72 Speed 25 ft.
Insanity. The Pudding King has advantage on saving throws against being charmed or frightened.
Stone Camouflage. The gnome has advantage on Dexterity (Stealth) checks made to hide in rocky terrain.
Slime Lord’s Rot. Oozing pustules herald the first stages of this disease, which ends with the victim’s collapse into a pool of ooze ready to serve its new master. The character must make 6 successful DC 14 Constitution saving throws after a long rest before 3 failures. Each failure has a different effect.
Onset: Initial Effect: The target loses a hit-dice that it cannot regain until cured of the disease. In addition, the target is slowed.
First Failure. The target loses another hit-dice and 1d4 Constitution points.
Second Failure. The target loses 1d4 hit-dice and 1d6 Constitution points.
Third Failure. The target dies and collapses into a puddle of ooze ready to serve its new master Juiblex as a random type of ooze.
Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target.
Hit: 8 (1d8 + 4) acid damage and the target is exposed to Slime Lord’s Rot.
Slime Orb. Ranged Weapon Attack: +6 to hit, range 100 ft., one creature.
Hit: 14 (2d10 + 4) acid damage and the target is exposed to Slime Lord’s Rot.
Create Slime (Recharges after a Long Rest). The Pudding King creates a patch of green slime as a bonus action. The slime appears on a section of wall, ceiling, or floor within 30 feet of the Pudding King.
Virulent Pustules (Recharge on 5 or 6). Ranged Weapon Attack: +6 vs Constitution, range 100 ft., one creature. Hit: 20 (3d10 + 4) acid damage and the target is exposed to Slime Lord’s Rot. This attack targets Constitution, not AC. In addition to the necrotic damage, it does 5 poison damage per turn for 1 minute or until a successful DC 14 Constitution save is made at the start of the targets turn. In addition, the target is exposed to Slime Lord’s rot. Each time a saving throw is failed each of the target’s allies adjacent to the target takes ongoing 5 poison damage (save ends) and is also exposed to Slime Lord’s rot.
Rain of Effluvia. The Pudding King makes it rain filth and acid in the immediate area (up to 50-foot radius sphere). Each creature in that area must make a DC 14 Dexterity saving throw, taking 14 (3d6+4) acid damage and becoming blinded for 1 minute on a failed save, or half as much damage and not blinded on a successful one. Creatures of the ooze subtype and worshipers of Juiblex are immune to this effect.
Spawn of Juiblex. Once reduced to 0 hit points The Pudding King magically transforms into a black pudding with maximum hit-points. He reverts to his true form if he dies. Any equipment he is wearing or carrying is absorbed by the new form. In ooze form, the Pudding King retains his alignment, and Intelligence, Wisdom, and Charisma scores, as well as his action (including spellcasting). His stats and capabilities are otherwise replaced by those of the new form.
The so—called Pudding King holds court In the deepest sections of Blingdenstone. He was part oi the first settler mission led by the Diggerniattoeks, but the other svirfneblin soon shunned him for his many disturbing habits. among them his preoccupation with capturing and studying oozes, and his penchant for stealing and hoarding food until it rotted and then talking to it. The shunned deep gnome eventually struck out on his own. He spent years living among the oozes of the region, eventually subjugating a black pudding he calls “Princess Ebonmire” and a grey ooze he calls “Prince Livid. When the demon lords arrived in the Underdark, he followed the oozes drawn by ]uibilex’s presence, immediately throwing himself down before the Faceless Lord and pledging his eternal loyalty, His previous name and existence ended in that moment. and now there is only the Pudding King. Juiblex granted the Pudding King the power to summon and command oozes, then ordered him to return to Blingdenstone and claim it as part of the Faceless Lord’s new domain.
The Pudding King slipped back into the closed—ofi areas of Blingdenstone and set up court, summoning all manner of oozes along the way and rendering portions ul the ruined city uninhabitable and dangerous to outsiders. Utterly insane and channelling a terrible power, the Pudding King sits upon his throne with his “children” at his side. summoning ever more loyal subjects with each passing day. When he is ready, he will send them forth to cover and devour everything, transforming Blingdenstonc and its people into one giant mound of slime and goo formed.
DC 25 Perception: You notice the Pudding King’s skin quiver ever so slightly as if something is moving beneath his skin.