Special elementals

Jittering sulfur

HD: 1
Found: 1d6 near hot springs

Appearance: a rough, flaking ball of yellow powdery stone, with spindly limbs jutting and bending in all directions.
Wants: to run around enclosed spaces
Tactics: chaotic

Attack: 0
Defense: +1
Speed: +4

Abilities

1. Ram: light damage
2. Scattered essence: each round the it spends in melee with someone holding a source of flame, there is a 2 in 6 chance the sulfur in the air will ignite and burn into heavy black droplets. The flame will spread to all areas it has passed through, dealing 1d6 damage each round to anyone actively fighting in it, or 1 damage if they are focused on avoiding it. The elemental takes 1 damage per round while on fire, and will run around in a panic.

(I drew this one a while ago, but it's way too faded to look any good)

Ash angel

HD: 1
Found: 1d6 underground, in large buildings, or places where the air is particularly still.

Appearance: a winged, crumbling figure. Penitent and cautious in its posture and movements.
Voice: weak and rasping
Wants: stillness and quiet, stronger elementals to follow.
Tactics: careful but ill-considered

Attack: 0
Defense: +1
Speed: +2

Abilities

1. Smog: 1 damage, ignoring defense.
2. Burst: when killed, each will explode into a cloud of choking, obscuring ash that hangs in the air, sticking in the eyes and throat. For each Ash Angel killed in the same room, combatants of flesh fight with -1 attack and defense.

Hovering spirits thought to be closely related to wraiths, they likewise prefer the still and silent. They are quite vulnerable to strong winds or water (a bucket or more), which can dissipate them without letting them burst.

Reforming by Aaron Salter

Forking fiend

HD: 5
Found: solitary at places where the future could go many ways.

Appearance: countless little spindly limbs meet at a joint, which reaches up to do the same again, creating a sort of pyramidal centipede without head or segmented body.
Voice: crackling and uncertain
Wants: possibility. It likes forks in the road at least, but will seek greater possibilities
Tactics: random

Attack: +3
Defense: 3
Speed: +3

Abilities

1. Dagger feet: light damage
2. Splitting: when it takes one third of its damage, a HD 1 forking fiend splits off and fights alongside it, with 1 attack, defense, and speed bonus. Likewise its stats decrease by one each. Happens again at two thirds damage.

Hungry forge

HD: 4
Found: where many dwarves have died

Appearance: ponderous blocky limbs heaving a tall, rounded body. A chimney spews smoke from above and a mouth glows from red hot coals within.
Voice:
Wants: to eat metal
Tactics: cautious

Attack: +1
Defense: +2
Speed: -1

Abilities

1. Mulch: it will take metal into its furnace and smelt it down, stopping for a round to smelt a random tool (1. shovel 2. plates & cups, 3. hammer & nails 4. chain 5. light struts 6. small chair). If it hasn't forged anything recently, it will aggressively try to take weapons and/or armor for this purpose, but is not picky if offered metal.
2. Hammerblow: medium damage.
3. Spew: 1d6 fire damage, agility save for half. Cannot act next round as it stokes the flames.

Gold-Forge Garrison by Svetlin Velinov

Annihilatrum

HD: 2
Found: solitary at sites of great magical destruction or natural disasters

Appearance: a roiling, heavy smoke with embers glowing from within and electrical energy crackling about its long limbs.
Voice: booming and sudden
Wants: to discuss the nature of destruction and preservation, and kill immortal beings.
Tactics: aggressive

Attack: +4
Defense: -1
Speed: +3

Abilities

1. Flaming thunder: red hot talons of crackling energy form, dealing heavy damage.
2. Destructive existence: when moving slowly, it can pass through unattended solids, completely destroying them.

Photo by Francisco Negroni

Luminbeast

HD: 2
Found: solitary at the depths of the Temple of Hidden Light

Appearance: broad shouldered shining form, fading into shadows from the waist down. Without light nearby it looks wan and frail, but as it absorbs lights it fills out, appearing more muscular and sturdy.
Voice: slightly echoing
Wants: to collect candles and kindling
Tactics: aggressive

Attack: +1
Defense: 0
Speed: +1

Abilities

1. Luminous form: for each light source roughly as bright as a torch or three candles, the Luminbeast gains +1 HD, attack, defense, and speed. One round after such a light source is extinguished, these bonuses are lost.
2. Raking light: shimmering claws that deal light damage.
3. Great flare: a blinding burst of light shines from its body, blinding anyone nearby. 2 in 6 chance this drains a light source, extinguishing it.

Lush soul

HD: 1

Found: 

Appearance: crudely humanoid shape, plump and welcoming, formed of alcohol as if held by totally unseen glass.

Voice: bubbly and muffled

Wants: strong alcoholic drinks, to join diverse groups

Tactics: careful

Attack: +1

Defense: +2

Speed: +0

Abilities

1. Slam: light damage. Coats target in flammable alcohol on a successful hit.
2. On tap: regrows about 5 liters of alcohol a day, up to its normal size at 50 liters. It will fight if half of it is consumed.

Beer Dragon by Nicolás Morales
Not the same idea, but a good beer elemental

Dashhoop

HD: 1

Found: 1d6 in flat expanses of firm ground, as large as possible

Appearance: translucent wheel of lightning, peeling wildly and without rest.

Voice: screeching

Wants: to race

Tactics: distracted

Attack: +1

Defense: -1

Speed: +8

Abilities

1. Ram: medium damage.

Able to attack while moving, but cannot but move every round. If someone races to a target, it will be unable to resist competing against them.

Silvery doppelganger

HD: 3

Found: solitary in heavy concentrated metal veins

Appearance: angular, metallic humanoid covered in flat, shiny surfaces. Whoever is close enough to be reflected will find themselves fighting their own mirror image, reaching through the surface.

Voice: scraping and faintly echoed

Wants: to show reflections

Tactics: whatever it thinks the foe will use

Attack: +1

Defense: +2

Speed: +1

Abilities

1. Reflection: each person fighting it in melee will fight their reflection, with their bonuses added to its own for them alone. If approached peacefully when not in combat, by someone who hasn't attacked it, the reflected selves will only try to assist with grooming, examination, or what have you.