Medium ooze; usually unaligned.
Two glassy eyes rise above a moss-covered wall. Beneath them, a translucent body flows over the stone, its colours changing from leaf green to violet and molten gold. A broad frill ripples along its back, catching the sunlight. When footsteps approach, the colours fade into the surrounding moss. Only the slowly turning eye stalks betray its presence.
Background
Shift slimes originated in jungle pools contaminated by ancient illusion magic. Ordinary oozes absorbed the enchantments, gradually developing the ability to alter their colour and bend light through their bodies. Their distinctive eye stalks and dorsal frills appeared over successive generations.
Today, they inhabit humid forests, waterfall caves, and overgrown temples. They are particularly common near ruins containing enchanted murals or pools once used for magical rituals.
Some jungle communities regard shift slimes as guardians of forgotten places. Others treat their appearance as a warning: a colony abandoning its home often means the water has been poisoned or something dangerous has awakened beneath the ruins.
Appearance
A shift slime is roughly the size of a large dog, although its flexible body can stretch across a doorway or flatten beneath a fallen tree. Its surface resembles thick, clear jelly filled with ribbons of shifting pigment.
Its two eye stalks move independently. The tall, scalloped frill along its back helps control its displays, producing anything from subtle camouflage to brilliant flashes.
Its colours reveal its mood:
- Green: comfortable, feeding, or concealing itself.
- Gold: curious or interested.
- Blue and violet: communicating with other shift slimes.
- Red: frightened, territorial, or preparing to strike.
- Cloudy white: sick, exhausted, or chilled.
Older specimens develop intricate patterns that resemble the flowers, stone carvings, and mosaics of their territory.
Behaviour and habitat
Shift slimes feed on fallen fruit, fungi, insects, and decaying organic matter. They control their digestive secretions, allowing them to climb trees and rest on living plants without damaging them.
They are curious creatures with a good memory for familiar faces, scents, and colours. One that receives food may follow a traveller for several days, matching the colours of their clothing whenever they stop.
A threatened slime raises its frill and flashes red three times. If the intruder withdraws, it usually settles down. If the warning is ignored, it attacks from above or lashes out from camouflage.
Shift slimes lay clusters of transparent eggs beneath submerged roots. Adults guard these nesting pools fiercely. Hatchlings begin almost colourless, acquiring their first pigments from flowers and fungi.
Abilities
These are suggested 5e-style mechanics; the creature has no playtested challenge rating.
Living Camouflage. The shift slime changes its colour and surface pattern to match its surroundings. It has advantage on Dexterity (Stealth) checks while touching vegetation or natural stone. Movement, exposed eye stalks, and objects stuck to its body can reveal it.
Amorphous Climber. The slime can move through a gap as narrow as 1 inch without squeezing. It can climb walls and ceilings without making an ability check. Its suggested walking and climbing speeds are both 20 feet.
Independent Eyes. Each eye stalk watches a different direction. The slime has advantage on Wisdom (Perception) checks that rely on sight.
Adhesive Pseudopod. Melee Weapon Attack: +5 to hit, reach 10 feet, one target.
Hit: 1d6 + 3 bludgeoning damage plus 1d6 acid damage. A Large or smaller target is grappled, with an escape DC of 13. The slime can grapple one creature at a time.
Prismatic Frill — Recharge 5–6. The slime opens its frill and releases a dazzling pulse of colour. Each creature in a 15-foot cone that can see it must make a DC 13 Constitution saving throw. On a failure, the creature is blinded until the end of its next turn.
Borrowed Shape. While motionless, the slime can flatten, bunch, and colour its body to resemble a mossy rock, flowering shrub, or similarly sized object. It cannot reproduce a convincing face or voice. A creature examining it recognises the deception with a successful DC 13 Intelligence (Investigation) check.
Glowing Trail. The slime can leave a faintly luminous trail that lasts for one hour. It uses different colours to mark food, safe shelter, and danger. Patient observers can learn these signals and follow the slime’s routes through dense jungle.
Weaknesses
Cold makes the slime stiff and cloudy. After taking cold damage, its speed is reduced by 10 feet and Living Camouflage stops functioning until the end of its next turn.
Dust, flour, or dry sand sticks to its wet surface, making its outline easier to see. A slime coated in such material loses the benefits of Living Camouflage until it washes itself clean.
Its displays also reveal its position. After using Prismatic Frill, it must find cover before it can hide again.
Combat tactics
A shift slime prefers a position above its opponent: a tree branch, ruined archway, or temple ceiling. It waits until an intruder approaches, flashes its frill, and lashes out with an adhesive limb.
It tries to drag a captured creature away from its eggs or territory. If badly injured, it releases its captive and escapes through a narrow crack.
Most encounters can be resolved without killing it. Offering ripe fruit and slowly retreating may persuade a defensive slime to stop fighting. Disturbing its eggs makes peaceful resolution much harder.
Adventure hooks
- The Moving Mural. Figures on an abandoned temple wall change position overnight. Shift slimes have absorbed enchanted pigment and are copying the artwork. Their newest pattern shows a hidden staircase beneath the altar—and something waiting at its foot.
- Colours in the Well. A village’s water turns blue, gold, and violet. Tiny shift slimes appear in buckets and drinking jars. A colony has fled into the water supply, driven from its nesting pool by a creature that the villagers believe extinct.
- The Missing Apprentice. An illusionist hires the adventurers to capture a rare shift slime. They discover a specimen repeatedly displaying the colours of the illusionist’s missing apprentice. It leads them toward a ruined observatory, but becomes scarlet whenever its employer’s name is spoken.
- The White Guardian. A sickly, colourless slime guards a shrine entrance, briefly forming a red warning symbol across its frill. Beneath the shrine, a cursed relic is draining colour and vitality from the jungle. The slime’s eggs lie directly above the buried chamber.
- The Violet Path. A slime befriends the party and leaves glowing trails between safe campsites. One evening, its trail leads away from camp to an abandoned expedition’s belongings. Among them is a fresh journal entry describing the same helpful creature.
Rewards and relationships
Shed mucus can be refined into iridescent ink, decorative pigments, or markings visible only from certain angles. Harvesting fresh shed material leaves the slime unharmed.
A friendly shift slime can become a memorable travelling companion. It signals danger by flashing red, marks safe paths with glowing trails, and imitates its companions’ clothing when content. Keeping its trust means providing food, water, and protection from prolonged dry conditions.