Masters of the hammer and axe, Giant Killers learn many techniques particularly suited to fighting giants. In the ages since the War of the Stones, they have discovered that their techniques can give them an edge in battle against anything larger than themselves (note that all of the children of the world fall into this category).
As it is graven in the Hall of Histories, on the Twelfth Deep of Haganduur, the oldest and greatest city of the Dwarves, south wall, fortieth panel, tenth register:
"And then Thurin, First Shaper, Father of Stones, bid his children cease in their labors, and journey from the deeps unto the Wide World, whose only roof is sky. Never before had any Dwarf seen the open lands above, or the vault of heaven filled with stars, and those that went with Thurin wondered at it. They journeyed to a mighty mountain, whose face was broken. There at the feet of the peak lay heaps of broken stones, all engraved with mighty letters and runes of power. And Thurin named the stones Runestones, and told the Dwarves the secret of their power, and bade them gather the stones and hold them fast in Haganduur, so that their power would not be lost. Also, he told the Dwarves of the treachery of the Giants, which had shattered the Cliffs of Fate, scattering countless more Runestones to the far corners of the World. The Shaper bid his children search the every realm for the Stones and bring them also back to Haganduur, so that the great design of his master the All-Father could be fulfilled. And so we, Thurin's chosen, the stewards of the deeps, gathered the Stones, and did Thurin's bidding. As we worked we read the stones, and learned their wisdom. The labor was a long one, for the broken stones had once spelled out the destiny of the World, from its beginning unto its uttermost ending. But Thurin's chosen were undaunted, and we labored long by night, singing as we worked.
After years of labor, our singing drew the Giants, who swept over the peaks like a storm. The earth shook beneath their great feet, and fell were their voices, raised in wrath. "Who are you, stunted mountain children?" Asked the chief giant, his voice grim as thunder. "Why have you taken these stones, the gift of our Father?" And Dorumbar Delver, Thane of Haganduur, answered. "Great Giant, we are the sons of Thurin, Father of Stones. We take these stones by his bidding, to do the will of the All-Father." And the Giant raged, so that the snow shook and roared down the mountainsides, and all the heavens darkened. "Thieves!" he cried, "I am Ymur Giant-king, born first of all Giants, made by the hands of the All-Father himself! Ours were the hands that carved the great Saga. The Runestones and all the power within them is ours by right!" And Ymur and his kinsmen fell upon them, and sundered every Dwarf they could find. Dorumbar they cleaved with mighty axes, and Hingorn was crushed beneath their feet, and Keldron the Forge Master, and Findo True Axe, and Vashtarn Granitebrow, and...
(The list proceeds through ninety-one more names. The chronicle continues on the South Wall, 48th panel, 12th register.)
Of all that had labored under the stars, only Gutthorm escaped, and fled to the Halls of Thurin to warn his people.
Thus it was discovered that we Dwarves, too, could die. And die they did, in numbers eight times twelve. Never, in all the Times Before or the Age of Twilight, had a Dwarf ever met his end, not even at the Dragon's rising. And all of Thurin's children despaired. Our sorrow took voice, and thus did we, the Sons of Earth, make a new song, the Song of Mourning.
But the Dwarves were yet undaunted, and would not leave their task undone. And so Thrangdan Stoneshoulders went to the store of weapons the Forge Masters had crafted and laid aside, and took therefrom mighty weapons and arms. When he emerged, Thurin's folk wondered at him, for in those days the Dwarves know only craft and shaping, and had no words for war or warriors. "Thurin our Father bid us craft these weapons that we might be ready for the return of the Dragon," Thrangdan called to his folk, " but now we have learned there are other dangers in this World. We have forged the weapons, and now I shall use them, for surely it is his will that I protect myself and my brethren. I hereby set aside my duty, and will take another. If my deeds anger Thurin, let the sin be mine alone." The Dwarves were stunned at Thrangdan's fiery words, but the Warrior continued. "Today I take a new name, may it echo in these halls forever," Thrangdan cried. "Call me Thrangdan Giant-Killer!" And others followed him, and soon five hundred Dwarves in coats of mithril and helms of adamant stormed out of the Earth, armed with stout hammers and grim axes, and the Giants quailed at their coming.
So began the First War, the War for the Stones, that grim war in the frozen North. So Thurin's folk learned the arts of battle and of war, and hands made for crafting turned to killing, and people born to live forever learned how to die. Many new verses have been added to the Song of Mourning, one for each hero who lives no more. Mighty were the Giants in those days, and many great Dwarfholds and Halls were broken and unmade by their strong hands. But ever the Giant-Killers were there to match them, and learned quickly how to fight even these greatest of foes. And so the Giants learned to fear Thurin's folk, and to this day tremble at the voices of the Giant-Killers, howling for vengeance."