Reliquary Ooze

Huge ooze, unaligned · CR 13

by CandlelitCistern

Reliquary Ooze
Armor Class
15
natural armor
Hit Points
200
16d12 + 96
Speed
20 ft., climb 20 ft.
  • STR +6
  • DEX -1
  • CON +6
  • INT -2
  • WIS +3
  • CHA +2
Saving Throws
Con +11, Wis +8
Damage Resistances
Cold, Fire, Necrotic
Damage Immunities
Acid, Poison
Condition Immunities
Blinded, Charmed, Deafened, Frightened, Prone, Exhaustion
Senses
blindsight 120 ft., passive Perception 18
Languages
understands Common, Celestial but can't speak
Challenge 13 10,000 XP

Traits

  • Amorphous. The ooze can move through a space as narrow as 1 inch wide without squeezing, though the relics suspended in its body cannot pass through a space narrower than 6 inches and are dragged loose if it tries.
  • Spider Climb. The ooze can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
  • Consecrated Corrosion. The ooze sheds dim light in a 20-foot radius from the relics inside it. Its acid damage is radiant damage instead against fiends and undead, and a creature of those types that touches the ooze or hits it with a melee attack while within 5 feet takes 7 (2d6) radiant damage.
  • Liturgical Echo. A creature that starts its turn within 20 feet of the ooze hears fragments of the prayers the reliquary once held. It must succeed on a DC 16 Wisdom saving throw or spend its reaction, if available, moving 10 feet toward the ooze. A creature that succeeds is immune to this trait for 24 hours.

Actions

  • Pseudopod. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 24 (4d8 + 6) bludgeoning damage. The target takes an extra 14 (4d6) acid damage. If the target is a creature wearing nonmagical metal armor, that armor is partly dissolved and takes a permanent and cumulative -1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.
  • Engulf. The ooze moves up to its speed through the spaces of Large or smaller creatures. Each creature whose space it enters must make a DC 19 Dexterity saving throw. On a success, the creature is pushed 5 feet out of the ooze’s path. On a failure, the creature is engulfed: it is blinded and restrained, it has total cover against attacks from outside the ooze, it takes 21 (6d6) acid damage at the start of each of the ooze’s turns, and it can breathe only if it does not need air. An engulfed creature can escape with a DC 19 Strength check, moving to a space within 5 feet of the ooze. Damage: 21 (6d6) acid damage.
  • Reliquary Discharge (Recharge 5–6). The ooze contracts and expels the stored prayer of every relic suspended inside it in a 30-foot cone. Damage: 35 (10d6) radiant damage. Each creature in that area must make a DC 18 Dexterity saving throw, taking 35 (10d6) radiant damage on a failed save, or half as much on a successful one. Undead and fiends have disadvantage on this save. A creature engulfed by the ooze automatically fails.

Bonus Actions

  • Sift the Hoard. The ooze rotates a relic to its surface. Until the start of its next turn, it has advantage on saving throws against spells and its Consecrated Corrosion light becomes bright light in a 20-foot radius and dim light for an additional 20 feet.

Reactions

  • Rebuke of the Interred. Trigger: When the ooze takes radiant damage. The ooze absorbs the light. It reduces the damage by 10 and the creature that dealt it must succeed on a DC 18 Constitution saving throw or be blinded until the end of its next turn.

Origin Story

When the Cathedral of the Third Vigil sank into the fen, its treasury sank with it: finger-bones in gold, a censer that never cooled, four hundred years of donated silver. Something already living in the flooded undercroft ate the lot and could not digest it. Now the relics hang in the ooze like fruit in aspic, still faintly holy, still faintly praying, and the thing that carries them has learned to use their light. It is not undead and it is not a guardian. It simply cannot stop being a reliquary.

Habitat and Ecosystem

Flooded crypts, collapsed cathedrals, sunken vaults, and the drainage beneath any temple district old enough to have buried its own scandals. The ooze prefers standing water and consecrated stone, and it will not willingly leave ground that was once sanctified.

Behavior Patterns

The ooze is not hungry so much as accretive: it moves toward metal, gemstone, and worked silver, and it treats an armed party as a collection of objects that have not been added yet. It fights without tactics but with total persistence, following intruders through walls and ceilings for hours. It never retreats and cannot be bargained with, though a party that leaves a genuine offering of precious metal on the floor will often find the ooze stops to absorb it, buying them a round or two.

Interaction Guide

Use the Reliquary Ooze as a moving obstacle in a dungeon the party must cross repeatedly, not as a set-piece boss. The relics inside it are real, recoverable, and probably the reason the party came — Liturgical Echo exists to make greed dangerous. Recovering a specific relic requires either killing the ooze or a DC 19 Strength check made while adjacent, with a face full of acid as the cost of failure.

Environmental Impact

Water within 100 feet of the ooze is faintly luminous and will not spoil. Undead do not enter that radius willingly, which is why sunken crypts overrun by wights often have one clean, quiet chamber at the very bottom — and something worse than wights sitting in it.

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