(Note: Lumping giant humanoid creatures into two broad categories -- essentially "Earth Giants" and "Not Earth Giants" -- is almost as arbitrary as grouping humanoid creatures by their bulk and height. Nevertheless, some division must be made, and this seems to be a useful one. The term "legendary giants" is more appropriate on the Fire Coast however than in places like Grat'ha, where cyclopes, at least, far from matters of nebulous legend, are known to exist beyond question.)
By far the most common humanoid giants are those collectively known as earth giants, but legends persist of others with strange features or powers, perhaps developed over the course of centuries or millenia by the ancestors of these giants themselves, or perhaps originated by powerful sorceries or ritual magics that transformed one or more communities in their entirety. Black Steel personnel have managed to locate unmistakable living cyclopes on several occasions, and have on a very few occasions (including very recently in the course of Herring and Theril's present journey through the jungles of Grat'ha) spotted a giant of enormous size that for one reason or another they supposed might be one of the so-called "fire giants" -- whatever that designation means.
Cyclopes are popular subjects of fables along the Fire Coast, which -- as fables usually do -- disagree rather thoroughly about their numbers, lifestyle, size, and intelligence. Black Steel personel have encountered several live cyclopes however, particularly in the region of Grat'ha, and have therefore come to a tentative conclusion that these monstrous one-eyed giants -- monstrous on the strength of their size alone, with some over six meters in height -- actually represent a viable, breeding species, which survives in the fertile lands of Grat'ha in a fashion roughly similar to that of "mountain giants" in more arid climes. The story of these creatures' origins is likely an intriguing one if it could be uncovered, as it is hard to imagine a one-eyed race of giants coming to be unless as the result of extraordinarily powerful sorcerous forces. Those Fire Coast myths that refer to these creatures' origins at all typically speak of a terrible pantheonic curse. Cyclopes encountered by Black Steel to date have mostly been aggressive and dull-witted by human standards, and certainly incapable of wielding sorcerous power, but these numbers remain too small to draw serious conclusions, in spite of the close contact Black Steel personnel have had with them -- including three that were coaxed by magic (and then slowly weaned from their bewitchments) to join Black Steel's forces themselves. The needs of these gigantic creatures are so enormous that, when not provided by a more civilized and far-reaching entity like Black Steel, they leave cyclopes as necessarily solitary or near-solitary creatures, likely meeting only to bear and raise children in the fertile, food-rich jungles themselves. It is therefore likely that few traditions of any kind are passed down beyond the bare necessities of survival, leaving open the theoretical possibility of magical aptitude that simply but inevitably goes undiscovered, unnurtured, and untaught.
Talk of magic-wielding giants on the Fire Coast comes in many varieties, but the most common references -- particularly in the far north -- are to "Fire Giants" who live in the deeps of that land's volcanoes, and cause eruptions when they go to war, and to "Frost Giants" who bring the winter each year (and against whom, many legends tell, Shaer and/or Athoth do annual battle, to force their retreat and permit the spring to return). They are said to be the personal servants of Karha, the Winter Maiden, whose beautiful ice palace -- sometimes spoken of as a place in the far north of the world, other times as her home beyond the world in the realms of the pantheon -- stands at the heart of many legends of its own. Fire Giants are likewise sometimes said to be the servants of Varekh, but sometimes to be renegades from his rule of the earth and stone. Reports of the powers, size, and strength of these giants vary, and if Black Steel personnel have ever met such a creature, they saw no sign of any particular power. Some claim to have seen a fire giant walking the streets of Night Harbor, but have no proof that it was such a creature apart from its being "huge!" and its bright red hair. Herring and Theril recently met a giantess deep in Grat'ha as well with dark skin and blood-red hair, estimated at five meters in height or more, but were not able to communicate with her. She spoke to them in a language they did not know, climbed the massive tree where they were perched, and settled herself in a kind of saddle formed by the stumps of its fallen upper branches, apparently to watch the jungles around her (a sentry, perhaps?) or just to relax in the sun. She or others like her might explain Grat'han tales of "fiery" or "fire-head" giants, but it is difficult to establish any connection between these tales and the "fire giant" legends of the north.
Other tales speak of giants capable of walking invisibly across the world -- how even an invisible giant could actually pass unobserved among humans is rarely addressed in the tales -- watching the doings of distant lands, raining magical forces down on their enemies, or transforming themselves or their victims into beasts, structures, or stones, among other incredible powers. If such stories have any basis in truth, it has not been confirmed or discovered by any Black Steel personnel.