Ancestor Steel

In the western reaches of the Northern Continent, humans give offerings to the gods at regular intervals throughout the year, regardless of how pious a particular settlement tends to be on the whole. By long-standing custom, the meat of slaughtered animals is eaten during the festival attending the sacrifice, and is carefully removed along with the skin to be used by the people. Unusable parts and the blood is all reserved for the gods, with the latter poured over statues and the earth while the rest is burned in a special fire. The exception to this is the bones of bears, dire wolves, and other animals that distinguish themselves in the minds and imaginations of humanity, for their bones are used to create steel, as smiths fold the carbon into iron while murmuring prayers used over millennia. The steel lends itself to magical enchantment as though it was bronze, though the magic is of the kind favored by the unMarked. 
Another more rare variant of this steel comes from the remains of distinguished ancestors themselves. Custom dictates that the bodies of the virtuous be unmolested for fifty years, after which the bones may be exhumed for this purpose. The bones of one's ancestors make for an especially spiritual steel, one reputed to defend the wielder against certain magics and being capable of cleaving ephemeral forms or steel shields as if either were paper. Ancestral steel like this is best in the hands of descendants, and most cultures view wielding another's ancestral sword or spear as a grave insult and social taboo. Siblings and cousins have fought each other to the death on occasion for the right to bear one of these arms. Not every man or woman leaves behind a legacy worthy of capturing their valor in a blade, making these swords among the most rare and cherished heirlooms in the world. Those who wield a blade like this in their lifetime often hide the blade or leave it behind a series of trials instead of passing it on to a direct descendant, so that anyone who bears it in the future must prove their worth. Some of the legendary blades known in legend are:
Freagróir - The Answerer, a blade borne by the first Queen from the Shield region to fight the Republic in its earlier days. Anyone who landed a blow on her was immediately struck down by this fantastic sword as it shore through armor, shield, and flesh.
Rindreáil - The Render, a spear known for causing wounds that would not close under any magic or natural force. The great warrior who first wielded it, Sionnach Cheeksplitter, famously turned the tide of a battle by dashing through enemy lines leaving superficial wounds on hundreds of men, all of which drained them of vitality until they were eventually defeated.
Grýlukerti - Affectionately called Icicle, this spear was first used by a young man tasked with slaying the dragon who invaded the region. Told that he must slay this beast or a wicked jarl would condemn his family to death, the hero was lead to the bones of his grandfather and it's said that a goddess herself forged the spear, which drains the heat from all it strikes. The dragon's fiery breath faltered, and every cut the hero made on the beast froze its blood, eventually stilling its heart.
Hringur - The Dancing Blade enables its wielder to expand their consciousness, remaining aware of all around them and never succumbing to surprise. The woman who first took up this sword lead her people for forty years and through numerous hardships, resisting no fewer than thirty nine assassination attempts.