Note: the following is taken from the introduction to Greenskins in the Mist, the seminal work on the beast tribes collectively known as goblins, by the Immortal Bard. All errors and opinions are his. This work does not necessarily reflect the views and opinions of the Scholar's Guild.
Most people hate and fear the goblins. Green of skin, short of stature, ugly, bestial--these are a few of the epithets hurled at these creatures. Even now, generations after the Cataclysm, they still get blamed for much of the devastation. As I will show, this characterization is unfair. Goblins are a beautiful race with strong desires for civilization.
Goblins, Hobgoblins, and Bugbears
Most know that there are three types of creatures commonly found in each tribe. Goblins, the smallest, weakest and most common, are barely the size of a halfling. Clever with their hands and inventive with traps, they are cowards and will only attack with overwhelming numbers. Hobgoblins form the core of the fighting force. Taller by far than goblins (about the same height as men or even orcs), hobgoblins are tactical leaders of the highest caliber. Their fighting style is organized and disciplined. It reminds me of the best armies from before the Cataclysm. Fortunately hobgoblins are much rarer. A large tribe of several hundred goblins might have ten or fifteen hobgoblins. Strangely enough, the leaders of the tribes are never hobgoblins despite their leadership qualities. The last type of creature is the bugbear. Huge and muscled, only male bugbears seem to exist. They are barely better than animals intellectually--only rarely can they speak in more than broken phrases. They seem to exist only for battle and for heavy labor. They are also quite rare (about half as common as hobgoblins).
The common idea is that these are three related species who have formed somewhat of a symbiotic relationship. The goblins labor and invent, the hobgoblins protect, and the bugbears are living weapons. I have discovered over my time living with various tribes that the truth is somewhat different. There is only one species. Goblins. The belief and needs of the tribe cause young goblins to mutate into the other forms as needed.
For example, I was present for a short-lived war between the Broken-Tooth tribe and a neighboring orc tribe. Before the war started, the Broken-Tooth tribe numbered about 400 individuals, with only 4 bugbears and 20 hobgoblins. Once the orc tribe started moving into the Broken-Tooths' territory and open hostilities broke out, the tribe still numbered about 400. Now, however, there were almost 250 hobgoblins and 50 bugbears. This changed over the space of a few months. I watched the tribe's shamans ritually endow young men (and women!) with charms--within days they were growing tremendously. I didn't sense enough magic for this to be polymorphing spells--the tribe was contributing aether from their own souls to accomplish this transformation. The effect on the remaining goblins was large--they were weak and listless. It seems that the creation and maintenance of the advanced forms puts a strain on the whole tribe. Once the war ended, the surviving hobgoblins reverted to regular goblins within a few months. The intellectual changes reverted as well. Sadly, those chosen to become bugbears did not survive the reversion process. The changes were too extensive. Once the tribe took back their aether, they started falling apart. Literally. Most died within days.
Goblins are a tribal people. Family is not important--the tribe is. I could find no pattern in their mating habits--no lasting family groups within a tribe. Goblin mothers produce 4-8 children every two years in optimum circumstances. The children are raised by the tribe. Mothers have no unique attachment to their children--they treat all of the tribe's young the same. About 25% of the young die within the first year. Young goblins are brought before the shamans of the tribe after their first year and given names. Those who will become either hobgoblins or bugbears are chosen at this time.
At their tenth year, children are considered adults. Males are traded to other tribes--exogamy is the norm. Only very rarely are male children kept by their home tribe. Hobgoblins and bugbears are never traded.
Even with ample food supplies, goblins don't live very long. The oldest one I have ever met had seen 65 summers.
The tribe is everything to a goblin. There is a sense of individuality, but it is subordinate to the needs of the tribe. They are intensely cooperative within a tribe--almost as if they share a common mind. Information is also shared incredibly quickly. I hypothesize that all goblins of a tribe are linked--they share aether in some way. Asking them about this is futile--they will not (cannot?) say how they know things that no one could have told them. They respond "gRa kaLa" (roughly translated as "I just know").
Tribes range from around 50 to over 500 persons. Small tribes get absorbed (usually peacefully) into larger ones; those too large for their territory hive off into smaller tribes. There does not seem to be any permanent group that controls inter-tribe behavior--squabbles and skirmishes are not rare when tribes compete for resources. Certain tribes have long-standing alliances with other tribes; intermarriage has little or no influence on tribal alliances.
Tribes are mostly nomadic. Some are settled, usually in fertile valleys and near mines. These settled tribes trade with the nomadic ones; very little other trade seems to occur. The nomadic tribes are hunter-gatherers or herders. Since goblins are aggressively omnivorous they can survive even on very poor ground.
Tribes are led by their shaman. This shaman is almost exclusively female. Their magic is akin to that of druids, but I have never seen one take the form of a beast. They intercede with spirits, they conduct divination, they point the tribe to new territories, etc. There doesn't seem to be much in the way of politics--they make decisions within a tribe almost without words and are united once they do.