Slurry (New Monster)

Slurry

Move: 30 feet/turn on land, 180 feet/turn in water
Hit Dice: 2
Armor Class: 2
Treasure Type: Q (gems only)

Alignment: neutral
Attacks: 1 blast of sandy water
Damage: 1d6

It is rumored that grizzled beachcombers search on forlorn shores for springs that bubble forth from the sand, because some such springs, if fed certain metals and a rough gem, will return the gem in expertly polished ovoid form.

Sages speculate that such springs are the temporary dwelling of a slurry, a small elemental haling from the Plane of Water, which has opened a gate from that plane in order to visit the Prime Material Plane in search of rare minerals to feed on. Being composed of primarily of water, but with an admixture of gritty sand, their natural form is amorphous and allows them to take on a variety of small watery shapes, be it sandy bubbling pool, eddy or spout.

Each turn that a creature is within the vicinity of such a spring has a 1 in 6 chance of drawing the attention of the slurry, unless it is fed as outlined below. The slurry will surface in the center of the waters and begin spraying the intruder with concentrated blasts of sandy water, once per round, until they retreat out of range (which is equivalent to a long bow). As with other elementals, a slurry can only be hit by magical weapons, and if it is destroyed, the gate will close in 1d6 rounds.

Living creatures that enter the churning waters of the spring will be able to swim, but will take 1 point of damage per round from the abrasive force of the sand in the water, unless they have a natural AC equivalent to chain mail or better.

Anything non-buoyant, yet lighter than fifteen pounds, dropped into the waters will bubble back to the surface in 1d6 rounds (1-9 in 10) or pass through the gate to the Plane of Water (on a 10). A gem treated in such a manner that resurfaces has a 1 in 6 chance of returning at the next higher value on the Gems table. Adding gold or platinum (10 GP worth) increases the churning of the pool as the slurry feeds on the metals, raising to 4 in 6 the chance of the gem increasing in value, but only once per day, and there is a 1 in 6 chance each day that it is fed that the slurry will be sated and depart to its home plane, closing the gate behind it.

Anything heavier than fifteen pounds that sinks into the waters has a lower chance of being ejected (1-8 in 10) passing to the Plane of Water (9 or 10 in 10). Furthermore, such an object will have a 3 in 6 chance of causing the slurry to surface in the middle of the pool and attack as outlined above.

Notes: 

(1) A slurry appears in Area 12 of the Forgotten Smugglers' Cave adventure.

(2) Inspiration for this monster comes from my childhood. A beach on a river near where I grew up had a spring that produced a tiny patch of bubbling sand several feet from the shore. We would push our plastic animals and dinosaurs several inches down into the bubbling waters (which we called "The Bubbly") and wait for them to be pushed back to the surface.