Crystal ooze is a variety of gray ooze (q.v.) that has adapted to live in water. When immersed, it is 75% invisible. Any dim or dark body of shallow water can be home to crystal ooze. It can exist out of water for several hours.

The attack mode of crystal ooze is to flow over a victim and exude a paralyzing poison. The poison causes damage as indicated above and, unless a saving throw vs. Poison is successful, the victim is paralyzed and will be consumed in a short time. When prey is reduced to -20 hit points, it has been totally consumed. 

Crystal oozes [are] unharmed by acid, cold, heat, or fire. Electricity does full damage as do magic missiles.

Blows from weapons do only 1 point of damage per hit. Wooden weapons are affected by the corrosive poison, and unless a save vs. acid (per hit) is used, they will be eaten off or break.

Medium-sized specimens have 16 hit points or less. Large ones have 17 or more hit points. Those with 28 or more are about 2-ft wide, 14-ft long, and six inches thick. [~875-lbs]

The gelatinous cube is one of the scavengers not uncommon in dungeons. Its cubic form is ideal for cleaning all living organisms, as well as carrion, from the floor and walls of underground passageways. Certain very large cubes are taller so as to be able to garner mosses and the like from ceilings as well.

Gelatinous cubes are nearly transparent and are difficult to see (thus surprise on 1-3). 

If a gelatinous cube touches (hits) an opponent, a saving throw versus paralyzation must be made, or the creature touched is anesthetized for 5-20 melee rounds. The 'cube then surrounds the victim, secretes digestive fluids, and digests a meal. Damage caused to opponents is due to the digestive secretions.

Gelatinous cubes can be hit by all forms of weapons, and attacks by fire have normal effects. 

Cold will have no effect on these monsters unless they fail their saving throw, in which case they are slowed 50% and do only 1-4 hit points of damage. 

Electricity, fear, holds, paralyzation, polymorph, and sleep based attacks have no effect on gelatinous cubes.

As these monsters travel about they sweep up metallic and other items which are "indigestible" to them. This includes treasure types J, K, L, M, N, Q as well as a potion, dagger, or similar items. Such material will remain in the body of a gelatinous cube for several weeks before being cast out (thus deposited somewhere on the floor).

Gray ooze is a slimy horror which inhabits subterranean places. It closely resembles wet stone or sedimentary cave formations.

They strike like snakes when attacking. This creature corrodes metal at the same rate a black pudding (qv.) does, i.e. chainmail is eaten through in a single melee round. Its acids do no harm to stone or wood. 

Spells do not harm this creature, and it is impervious to heat or cold. Lightning, however, causes full damage to gray ooze, as do blows from weapons. Note, however, that in the latter case the weapons striking the creature may corrode and break. 

Large specimens (over 18 hit points) are larger than a full grown man, some (those over 21 hit points) are fully 3-ft wide and 12-ft long, although only about 6 or 8 inches thick.

In exceptionally large individuals Intelligence of a sort is well developed. Furthermore, these exceptional individuals have a latent psionic ability, and if psionic powers are used within 6" of them they will prepare a psychic crush of from 21 to 121 psionic strength attack points and direct it at any individual within range who uses psionic abilities. After loosing its psionic attack the gray ooze can be psionically attacked.

Ochre jelly are a form of giant amoeba. They seep about in dungeons, hunting for any form of flesh or cellulose to devour — they far prefer the former. Their amorphous form allows them to flow through small spaces. They can travel along walls or ceilings with ease. 

The fluids excreted by these creatures dissolve flesh (3-12 hit points per round of exposure).

Striking the ochre jelly with lightning bolts simply divides the creature into one or more smaller creatures, each doing one-half normal damage.

Cold and fire based attacks have normal effect.

MUSTARD JELLY

Neutral Large Monster (ooze, plant) (9-12-ft dia.)

FREQUENCY: Rare

NO. APPEARING: 1

SURPRISE: 33%

SENSES: ooze senses

AURA: toxic vapor (10-ft)

ARMOR CLASS: 4

MOVE: 9" — see desc

HIT DICE: 7 + 14 (hp 46)

% IN LAIR: 35%

TREASURE TYPE: nil

THAC0: 12

MELEE: pseudopod (5d4)

SPECIAL ATTACKS: divide - Hits As: +2

SPECIAL DEFENSES: immune to acid and electricity, immune to magic missile (heals), plant traits, resist cold (half), DR/magic

MAGIC RESISTANCE: 65%

INTELLIGENCE: Average (8-10)

MORALE: +49%

SAVES: Poison 10, Petrify 11, Wand 12, Breath 12, Spell 13

LEVEL: VI (XP 825 + 18 per hp)

The mustard jelly is a strain of, or perhaps a relative of, the ochre jelly. The monstrous amoeboid mustard jelly, however, is far more dangerous. The only clue to its presence is a faint odor not unlike that of blooming mustard plants. That and its translucent yellowish-brown color give it its name.

Those nearby must save vs. poison each round, however, for the monster exudes a vapor within a 10-foot radius, and this toxic stuff causes victims to become lethargic and move at half-normal speed unless they save against the effect. Toxic effects last 2 rounds and are cumulative.

Normally, a mustard jelly attacks by forming a pseudopod of its acidic substance and striking with it.

This large ceature is able to divide itself into 2 smaller, faster halves (move 12-18"). Each is capable of attacking as well, but each has only half the hit points of the whole. A mustard jelly can, for example, flow into a room, divide itself into halves which are able to attack independently and simultaneously, and then form itself into torus-shape in order to surround a pillar which its prey has climbed.

It cannot move through small spaces, however, and it cannot move along ceilings as an ochre jelly can.

Mustard jelly is impervious to normal weapons, and electrical attacks and magic missiles cause it to grow. The mustard jelly gains hit points equal in number to the damage rolled. 

Cold causes only half damage; other attack forms are normal.

Although not unintelligent, mustard jelly is not known to value treasure of any sort. Of course, it is possible that some treasure might remain after a victim has been devoured.

Each form of deadly pudding is a variety of the better-known black (deadly) pudding, Acid, cold and poison have no effect on deadly puddings. Lightning bolts or blows from weapons divide these monsters into viable creatures of smaller size. Fire causes normal damage, as do magic missile spells. Details of each type are given separately below.

The black pudding is a monster composed of groups of single cells. It is a scavenger/hunter found only in underground areas normally. Black puddings sometimes have color variation, grey, brown, and white being not uncommon.

The body structure of a black pudding is such that it can pass (flow) through narrow openings (such as a 1" crack under a door). The monster travels equally well on walls or ceilings as well as floors.

Its tiny mouths and saliva do 3-24 hit points of damage per melee round to exposed flesh.

If the monster needs to dissolve wood in order to obtain food, it can eat away about a two inch thickness of wood equal in area to its diameter in 1 melee round.

Black puddings also eat away metal with their corrosive saliva: 

— Chainmail in 1 melee round, 

— plate mail in 2, and 

— an additional melee round for magical armor at a rate of 1 melee round for each plus of armor. 

Thus, +1 magic (plate) armor would have to be in contact with a black pudding for 3 melee rounds before it dissolved.

If chopped or struck, the monster is broken into two or more parts, each able to attack. 

The same is true if it is attacked by lightning.

Cold does not affect it. Fire causes normal damage to this monster, and they avoid flames.

Black puddings with 10-20 hit points are about 5-ft diameter, those of 21-40 hit points 6-ft, 41-60 are 7-ft, and 61-80 are 8-ft. 

Note that even those of the smallest size (or those as small as 1-ft diameter) are able to deliver normal damage. This is due to the fact that larger puddings simply do not use all of their mouth openings as they are not exposed.

These cold-dwelling creatures are 50% likely to be mistaken for snow and ice under the best of conditions. They haunt polar regions or icy places in order to find prey, although they can live by devouring any animal or vegetable material; even ice provides them with enough nutrition to exist. They do not affect metals but dissolve animal or vegetable materials in a single round, inflicting damage to flesh at an astounding rate. They are subject to attack forms as are all other deadly puddings.

SLITHERING TRACKER

Neutral Small Monster (ooze, plant) (2½-ft)

FREQUENCY: Rare

NO. APPEARING: 1 (V. 1)

SURPRISE: 33% — Others ~Auto

SENSES: ooze senses

ARMOR CLASS: 5

MOVE: 12"

HIT DICE: 5 (hp 23)

% IN LAIR: 10%

TREASURE TYPE: In lair C

THAC0: 15

MELEE: touch attack (no damage) plus paralysis

SPECIAL ATTACKS: paralyzation - Hits As: +1

SPECIAL DEFENSES: plant traits

MAGIC RESISTANCE: Standard

INTELLIGENCE: Average (8-10)

MORALE: +25%

SAVES: Poison 11, Petrify 12, Wand 13, Breath 13, Spell 14

LEVEL: V (XP 280 + 5 per hp)

This monster is transparent and almost impossible to discover (5% chance of spotting). It inhabits dungeons and other dark places, and does not normally attack its prey immediately (10% chance of immediate attack).

The tracker usually follows the chosen victim to the place where the victim sleeps, and only when its prey is asleep will it strike. 

Because of its semi-fluid body, the slithering tracker can flow through openings as small as a rat hole or a large crack under a door. 

Attack is by contact with the exposed flesh of its prey, and the secretions of the monster will paralyze the victim unless a saving throw versus paralyzation is made. Once the victim is immobilized the 'tracker will draw all the plasma from the body of its prey in 6 turns.