As mentioned before, my setting's goblins are more elf-like than usual, so I guess it fits to mention them.
Goblins
The elves and goblins were at one time a single people in the Dream Lands, and their civil war there caused them both to be expelled to the waking world, never to return. Both sides blamed the other for their exile, so they naturally dislike each other.
Where elves abandoned their shapeshifting ways, taking on new forms they still have in present day, the goblins tried very hard to keep their original shapeless forms. To that end, they bound themselves to shadow, water/mist, and smoke/flame. Each had an unfortunate side effect to the decision.
Those bound to water could travel from place to place by rain and vapor, but a strong wind pushed the clouds they were in to fall over a swamp. The trees were dense in that swamp, so they were unable to leave (no sun to evaporate). Not familiar with the area, they were unable to exit in time, and became bound to the swamp forever more. These swamp goblins still have some ability to shape themselves and their surroundings, but not being able to leave the swamp drove them a bit insane over the many many years stuck there. They have since learned to scry the outside world, and jealous of the humans and elves, they've created monsters of various form to send out and wreak havoc. In appearance, they look a bit like hairless wild elves, but with a slick slimy texture to their skin.
Those goblins that bound themselves to smoke and flame created great cities of lanterns and cook fires, inviting humans and other peoples to visit and warm themselves. Things were going well, until their queen heard from a visiting human that he had known of wood that could keep a fire burning forever. Wanting such magical wood for her people, she sent scouts to find and retrieve it. It was tracked back to the elves, their hated enemy. The elves would never give their foe such a prized resource, so the goblin queen felt it required to steal some instead. She had her goblins infiltrate and steal several pieces of the wood, but when they added it to the fires, they all snuffed out. Unbeknownst them, the enchanted wood was a gift from the gnomes. It came with both a blessing and a curse. Those gifted the wood can get the ever-burning effect the goblins coveted, but anyone stealing it would get the opposite effect: the fire would snuff out forever. Their fires gone, their power waned. Their visitors stopped coming and their cities crumbled away. Years later, they found a new home and new life in an active volcano. What they looked like previously is unknown in present time, but they now look similar to iron elves, but have hard craggy skin like molten rock and wisps of smoke in place of hair. These fire goblins are still in contact with some humans, especially those not fond of elves.
The most varied in look and culture were those that bound themselves to shadow. These goblins are tall, though not as tall and stretched in appearance as the high elves. Bound to shadow, they exude an aura that most people find unnerving. Shadows travel far and wide, so these shadow goblins did the same.
Some lived in caves, gaining purple skin and silver hair. These cave goblins, weaved magic into pools of still water deep underground. Though the intent was the pools to be used to transmute substances and objects for tools and resources, the pools eventually were used for more nefarious purposes. Cultists and dark mages have gained access to the shadow pools and performed rituals most foul, often involving blood sacrifices. All manner of monstrosities have crawled out of caves created by these rituals, the most well known of which are the trolls. The cave goblins themselves just mostly want to be left alone, but some of them have done dealings with dark gods, which is how cultists and others found out about the pools in the first place.
Other goblins chose living in dark woods, the ones humans and wild elves didn't want. Large spiders lived in these woods, which these goblins befriended. Over time their skin took on the same silvery-white as the spider's web, and their hair like dark green leaves. Some goblins used magic to fuse their blood with their beloved spiders to create a new creature that act as sentries to their homes, protecting from intruders. Mostly misunderstood, they have at times been drawn into war with those that disturb their home. They do have dealings with humans at times, as these goblins craft the most potent poisons known world-wide.
In addition to all these, some experimentation by the most evil of goblin kind into trying to create an army to conquer the known world, created other forms of goblin. The goblins I listed above all see these as "lesser" beings, mutants of all manner of size and shape. Small, mischievous goblins. Bulky, beast-like goblins. Even some with multiple sets of arms or legs. These outcasts are either taken in by tyrants and dark wizards as grunts and goons, or they form bands together on their own, raiding villages for what scraps they can get. Places where their blood is spilled and seep into the ground, more of their kind crawl out. A product of the foul experiments that created them.
