Capacitor Ooze — The Living Storm
At a Glance
| Creature | Capacitor Ooze — the living storm |
|---|---|
| Nature | Mindless, unaligned predatory slime drawn to stored lightning |
| Size | Medium; a viscous amber body veined with silver and blue sparks |
| Where found | Dry thunderstruck hills, old bell towers, desert ruins and sealed arcane vaults |
| Greatest danger | Shock on contact, nerve-stunning blows and devouring charged lightning |
| Warning signs | Faint static in the air, metal glowing blue, spent stormstones and scorched fingers |
| Company | Solitary; more may gather where storm magic is stored |
The bell starts ringing without a rope. Sparks crawl across its bronze rim. An amber mass drops from the tower stones, veined with liquid silver. The watchman strikes it with his sword, and blue lightning races down the blade before he can scream.
A Storm Trapped in Flesh
The ooze is translucent amber, threaded by silver veins that carry a cold, blue-white fire. It moves slowly until it detects a charged lightning focus, a stormstone in an alchemist’s chest or the vibration of nearby prey. An iron blade striking the body becomes a path for its current. The creature does not wield lightning with thought; its nervous violence is the only way it can feed and defend itself.
Lightning from its tendrils can make a victim rigid and senseless. A second blow to the helpless may leave trembling hands and damaged memory long after the burns have healed. A creature wrestling it or striking it with a bare hand may receive a shock strong enough to throw it backwards.
Dry Ground and Stored Storms
Most capacitor oozes favour dry, storm-struck country and ancient stone chambers where rain cannot reach them. A ruined hilltop beacon, a copper-roofed observatory or a vault of thunderstones may attract one. The floor is marked by scorch trails and a thin smell of heated air; puddles and running water discourage it. It does not drain an ordinary sword merely because it is metal. The danger comes from the electrical violence of its flesh and from objects deliberately charged with lightning.
What It Wants
The ooze feeds on organic matter and takes stored electrical energy whenever it finds it. It has no speech or purpose beyond this appetite. Two meeting in a sheltered ruin may merge into a larger mass; other pairs recoil from one another’s charge and crawl away across the stones.
Running the Encounter
Let the party discover its presence through a watch bell trembling, an old stormstone going dark or a guard being burned through his own weapon. Spears with wooden shafts, distance, dry masonry and escape routes matter more than brute force. Once it stuns a victim, it closes the distance for another jolt. Give the characters a chance to move their lightning-charged treasure beyond its reach before the creature finds it.
Game Statistics
Capacitor Ooze
Medium Ooze, Unaligned — original D&D 2024 adaptation
AC 14 (natural armor); Initiative +1 (11); HP 95 (10d8 + 50); Speed 30 ft., Climb 20 ft.
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 16 (+3) | 12 (+1) | 20 (+5) | 3 (−4) | 10 (+0) | 5 (−3) |
Saving Throws Con +8
Skills Perception +3, Stealth +4
Resistances Bludgeoning, Piercing and Slashing from nonmagical attacks
Immunities Lightning, Poison; Charmed, Deafened, Exhaustion, Frightened, Prone
Senses Blindsight 60 ft., Passive Perception 13; Languages None
CR 5 (1,800 XP; PB +3)
Traits
Amorphous. The ooze moves through gaps 1 inch wide without squeezing.
Electrified Body. When a creature hits the ooze with a metal melee weapon or an Unarmed Strike, that attacker takes 7 (2d6) Lightning damage. A creature grappling it takes this damage at the start of each of its turns.
Stored Lightning. The ooze drains one charge from a lightning-powered magic item, stormstone focus or similar deliberately charged object within 10 feet at the start of its turn, if its wielder fails a DC 15 Constitution saving throw. An affected item retains its other enchantments but cannot release lightning until the start of its wielder’s next turn. Only one item can be drained each round; this effect does not draw power from ordinary metal.
Actions
Multiattack. The ooze makes two Lightning Lash attacks.
Lightning Lash. Melee Attack Roll: +6, reach 10 ft., one creature. Hit: 12 (2d8 + 3) Bludgeoning damage plus 9 (2d8) Lightning damage. A creature that takes this Lightning damage must succeed on a DC 15 Constitution saving throw or have the Stunned condition until the start of the ooze’s next turn.
Shockwave (Recharge 5–6). Lightning erupts in a 15-foot Emanation. Each creature other than the ooze in the area makes a DC 15 Dexterity saving throw, taking 21 (6d6) Lightning damage on a failure or half on a success.
Bonus Actions
Consume Stored Spark. When the ooze successfully drains a lightning-charged item during this turn, it gains 5 Temporary Hit Points and 10 ft. extra Speed until the start of its next turn.
Capacitor Ooze
Medium ooze, unaligned — original D&D 2014 adaptation
Armor Class 14 (natural armor); Hit Points 85 (9d8 + 45); Speed 30 ft., climb 20 ft.
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 16 (+3) | 12 (+1) | 20 (+5) | 3 (−4) | 10 (+0) | 5 (−3) |
Saving Throws Con +8; Skills Perception +3, Stealth +4
Damage Resistances bludgeoning, piercing, slashing from nonmagical attacks
Damage Immunities lightning, poison
Condition Immunities blinded, charmed, deafened, exhaustion, frightened, prone
Senses blindsight 60 ft. (blind beyond this radius), passive Perception 13; Languages —; Challenge 5 (1,800 XP)
Traits
Amorphous. It moves through gaps as small as 1 inch without squeezing.
Electrified. A creature that hits it with a metal melee weapon or unarmed strike takes 7 (2d6) lightning damage. A creature grappling it takes the same damage at the start of its turns.
Osmotic Draw. At the end of each ooze turn, one creature within 10 feet carrying a lightning-charged magic item must succeed on a DC 15 Constitution saving throw or lose one charge from that item’s lightning effect. This does not affect normal steel or wood. The ooze gains 5 temporary hit points when it drains a charge.
Actions
Multiattack. The ooze makes two Lightning Lash attacks.
Lightning Lash. Melee Weapon Attack: +6 to hit, reach 10 ft., one target. Hit: 12 (2d8 + 3) bludgeoning damage plus 9 (2d8) lightning damage. The target must succeed on a DC 15 Constitution saving throw or be stunned until the start of the ooze’s next turn.
Shockwave (Recharge 5–6). Every other creature within 15 feet makes a DC 15 Dexterity saving throw. It takes 21 (6d6) lightning damage on a failure, or half on a success.
Capacitor Ooze — CR 11
XP 12,800; N Medium ooze; Init −5; Senses blindsight 120 ft.; Perception −5; Aura osmotic drain (10 ft., DC 25)
DEFENSE
AC 5, touch 5, flat-footed 5 (−5 Dex); hp 195 (17d8 + 119)
Fort +12, Ref +0, Will +0
Defensive Abilities electrified; Immune electricity, ooze traits
OFFENSE
Speed 10 ft., climb 10 ft.; Space/Reach 5 ft./5 ft.
Melee slam +18 (2d6 + 9 plus 4d6 electricity and neurophagic jolt)
Special Attacks neurophagic jolt
STATISTICS
Str 22, Dex 1, Con 24, Int —, Wis 1, Cha 1
Base Atk +12; CMB +18; CMD 23; Skills Climb +14; Feats —; SQ compression
ECOLOGY
Environment cold deserts or plains; Organization solitary; Treasure none
SPECIAL ABILITIES
Electrified (Ex). A creature striking it with a natural weapon, unarmed strike or metal weapon takes 4d6 electricity damage. A grappler takes the same damage on starting the grapple and each round that grapple continues.
Neurophagic Jolt (Ex). An opponent that takes electricity damage from the slam must succeed on a DC 25 Fortitude save or be stunned for 1 round. If hit by a second jolt while stunned, the victim begins suffering a resonance affliction: Will DC 25, once per round for 6 rounds, each failed save dealing 1d2 Dexterity and 1d2 Intelligence damage; one successful save cures it. This is a mind-affecting effect. Neutralize poison does not cure it, but heal, greater restoration or a cure for insanity does.
Osmotic Drain (Ex). At most once per minute for each power source, the ooze drains 1 charge from a random electrical device carried by a creature within 10 feet that fails a DC 25 Fortitude save. A one-use source is exhausted; renewable sources require recharging, and shock weapons may be suppressed for 1d4 minutes. Each successful drain gives the ooze an extra 1d6 electricity damage on its next electrical attack and increases its Speed by 30 feet for 1 round. This is the original Pathfinder rule for campaigns containing electrical devices; in a medieval campaign, a GM may instead apply it to deliberately charged lightning-magic foci or other rare arcane storm engines, leaving ordinary weapons and unrelated magic items unaffected.
Capacitor Ooze — CR 11
N Medium Ooze — original D&D 3.5e conversion
Hit Dice 17d10 + 119 (212 hp); Initiative −5; Speed 10 ft. (2 squares), climb 10 ft.
Armor Class 5 (−5 Dex), touch 5, flat-footed 5
Base Attack/Grapple +12/+18; Attack slam +18 melee (2d6+9 plus 4d6 electricity and neurophagic jolt); Full Attack slam +18 melee (2d6+9 plus 4d6 electricity and neurophagic jolt); Space/Reach 5 ft./5 ft.
Special Attacks neurophagic jolt, osmotic drain; Special Qualities blindsight 120 ft., electrified, compression, ooze traits, immunity to electricity
Saves Fort +12, Ref +0, Will +0; Abilities Str 22, Dex 1, Con 24, Int —, Wis 1, Cha 1
Skills Climb +14; Feats — (mindless); Environment cold deserts or plains; Organization solitary; Challenge Rating 11; Treasure none; Alignment always neutral
COMBAT
Electrified (Ex). A creature striking the ooze with a natural weapon, unarmed attack or metal weapon takes 4d6 electricity damage. The same damage applies to creatures grappling it during initiation and each round they maintain the hold.
Neurophagic Jolt (Ex). The slam forces a DC 25 Fortitude save or stuns for 1 round. A second jolt while stunned triggers a resonance affliction: DC 25 Will, one save per round for 6 rounds, 1d2 Dexterity and 1d2 Intelligence ability damage on each failure, cured by one success or appropriate restorative magic.
Osmotic Drain (Ex). Charged magical implements that store electrical energy within 10 feet must succeed on a DC 25 Fortitude save by their bearers or lose one stored lightning charge (once per source per minute). Each charge absorbed adds 1d6 electricity damage to the ooze’s next electrical attack and 30 ft. movement for a round. This is a 3.5e fantasy conversion of the original device-based Pathfinder ability.
What Is Happening Right Now?
The Bell Tower’s Stolen Storm
During a violent thunderstorm, a sorcerer’s lightning-charged copper rod is stolen from the bell tower without the door opening. The tower bells now ring when no one pulls them. Workers find scorch marks on the steps and a strange orange gel in the gutters. The castle’s watch cannot light the beacon while the thing feeds beneath the bells.
The Alchemist’s Glass House
An alchemist has been capturing lightning in sealed stormstones to heat a forge without coal. A crackling amber ooze has broken into the storehouse and drained every vessel. The tools are dead, the sealed doors are hot and the forge keeper has collapsed beside the fire. Opening the iron shutter will put every rescuer within striking distance.
Sources and Related Oozes
Pathfinder 1e source: Capacitor Ooze, from Pathfinder Campaign Setting: Numeria, Land of Fallen Stars, © 2014 Paizo Publishing, LLC (Jim Groves and Russ Taylor). The original Pathfinder rule for osmotic drain refers to electrical devices. The other three editions are original conversions; medieval adventure encounters use rare lightning-charged arcane objects, not modern gadgets.
Other oozes: Plasma Ooze · Gray Ooze · Black Pudding · Ooze Bestiary.
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