|Image by John M. Stater|
Edit: Now with crappy art by yours truly
The corundar are a silicon-based lifeform native to volcanic areas. They grow in and consume mineral salts in solution, but can survive on humanoid blood if necessary. Most corundar lair around a mineral spring, preferably underground, using the spring as a hatchery and as their main source of food.
Corundar consider themselves creatures of perfection. They attempt to beautify their lairs by making the walls, floors and ceiling smooth and angular. They likewise favor perfection in living creatures, both in mind and body. Corundar will always attack creatures with a combined intelligence and charisma score of less than 20, and always attack creatures with the lowest combined score first. Generally, three corundar will rush the imperfect creature, while others will circle them and provide defense until the imperfect specimen has been destroyed.
Corundar look like pyramidal lumps of crystal, about 3 to 4 feet in height and colored red, blue, orange or green. They are supported on four stubby, crystalline legs and have three long mineral straws protruding from their main body mass. These straws can move in the manner of tentacles, and are razor sharp on the edges. Corundar have tiny motes of light moving through their bodies, originating in their hollow center, where they maintain a pocket of mineral salt solution. They can control these motes as a means of communication (a difficult language to learn, requiring a minimum intelligence of 15). They can see with their entire bodies, making them very difficult to surprise. They can sense vibrations from the air and ground as well, making it possible for them to understand speech.
Corundar attack with their straws, whipping and slicing with them or using one of them to spray a corrosive solution of mineral salts (10-ft. long cone, 2d6 points of acid damage, save for half damage, usable once per day). Corundar are immune to acid and cold and suffer only half damage from fire and electricity.
Corundar (Pars Fortuna)
HD 4; AC 16; Atk 3 straws (1d6+1) or spray; Move 9; Save 13; CL/XP 6/400; Special: Immune to acid and cold, resistance to fire and electricity (50%), surprise on 1 on 1d10, acid spray (see above).
PC Race: +1 Con, -2 Dex; surprised on 1 on 1d10; acid spray 1/day, immunities and resistances; knack for finding secret doors
Corundar (Space Princess)
HD 4; DEF 16; FIGHT 10; SHOOT 7; MOVE S; STR 6; DEX 3; MEN 5; KNO 4; DL
PC Species: Mineral (new type, see below) / multiple arms and multiple legs (must spend 1 point of Luck to play a Corundar)
Mineral Alien: Mineral aliens are composed of rock or crystal. They have slow movement and DEF +2.
1. Empty Cavern: This cavern is untouched by the corundar, who use it as a buffer between their lair and the outside world; they have erected a crude “scarecrow” here – essentially a skeletal corpse on a slab of rock
2. Guard Post: Two corundar are always on guard here; when not otherwise occupied, they are grinding the walls with their straws
3. Low Cavern: This cavern hosts a hot spring that was insufficiently infused with minerals to serve the corundar; it is a 10-ft. deep pool of scalding water (2d6 damage per round) that sends a thick mist into area 
4. Guard Post: Three corundar are always on guard here
5. Workshop: Five corundar work here grinding stone into tools and other pleasing shapes and turning shed crystal into lenses for the temple
6. Temple: The corundar worship a clear crystal pyramid that represents perfection to them; small lenses are hung from the ceiling by thin chains; the temple is guarded by two corundar and the idol is attended by a priest who cast spells as a 5th level magician
7. Laboratory: The corundar high priest  maintains a laboratory here; the walls are carved into shelves holding various jars and beakers of mineral solutions; a vat has been carved from the stone in the center of the room – there is a 1 in 10 chance that it holds the makings of a potion
8. Guard Post: Two corundar are always on guard here
9. Forge and Foundry: This room contains a vent of super-heated, poisonous gas (the corundar are immune, of course, since they need not breath, but the gas does mar their appearance) that they use for purifying and working copper ore; there is a 30% chance that two corundar are here working
10. Mine: This cavern connects to a seam of copper that is mined by the corundar; there are usually 2d6 corundar here collecting the ore
11. Rest Chamber: Corundar need to sleep about 6 hours a day; this chamber holds 2d6 sleeping corundar
12. Mud Chamber: This chamber is filled with steaming hot mud; the corundar have created a pool for the mud and channels leading from the walls; they bathe in the mud when damaged
13. Guard Post: Two corundar guards
14. Vibro-Chamber: This space has acoustics that allow the corundar to create pleasant vibrations – in essence, a corundar concert chamber
15. Mineral Baths: There are 3d6 young here and 2d4 adults