Brokkr and Sindri

When Loki, freshly forgiven for shearing Sif, boasted that the sons of Ivaldi's treasures could never be equalled, the dwarf Brokkr wagered Loki's head that his brother Sindri could do better. Sindri worked the forge while Brokkr pumped the bellows, and Loki, hedging his bet, became a fly: he bit Brokkr's hand during the boar, his neck during the ring, and his eyelid — drawing blood — during the hammer. Only the last bite told: Mjölnir's handle came out short.

The gods judged the hammer the greatest treasure ever forged and the brothers winners. Loki saved his neck with a lawyer's parry — the wager was for his head, and no part of his neck might be touched — so Brokkr contented himself with sewing the trickster's lips shut with an awl. The scars, presumably, healed; the grudge did not.

Why Loki was betting his head in the first place

The whole episode begins with an earlier crime: Loki, for sport, crept in and cut off all of Sif's famous golden hair while she slept. Thor's fury left Loki no choice but to make it right, and he went to the dwarf smiths known as the sons of Ivaldi, who forged Sif new hair of living gold that would grow like any other, and threw in, unasked, two more wonders: the spear Gungnir, which never misses its mark, and the ship Skíðblaðnir, which folds like cloth yet always finds a fair wind. Delighted with the haul and, characteristically, unable to leave well enough alone, Loki went bragging about it to another dwarf, Brokkr, and declared that no smiths anywhere could match the sons of Ivaldi's work. Brokkr took the bait: he staked his own brother's skill, and Loki's head, on the wager.

The forge and the fly

The brother put to work was named, in Snorri's actual telling, Eitri — though this site follows the name Sindri that has become standard in later retellings and popular culture; in the older sources, Sindri is instead the name of the golden hall where the surviving dwarves are said to dwell after Ragnarök, per Völuspá, and the two names appear to have merged in tradition over the centuries. Whatever he was called, the smith set to work at a furnace fed by his brother's bellows, laying a pigskin, a lump of gold, and a bar of iron into the fire in turn, with strict instructions that the bellows not stop for anything.

Loki, having bet his own neck, was not about to leave the outcome to chance. He turned himself into a horsefly and attacked the one weak point in the operation — Brokkr's hand — biting hard enough to draw blood as the first item, a boar's hide, went into the flame; Brokkr never let go of the bellows, and out came Gullinbursti, the golden-bristled boar that would carry Freyr faster than any horse and light his way in darkness. Loki bit again, on the smith's neck, as gold went into the fire for a ring — and still the bellows never stopped, and Draupnir emerged, the ring that drips eight equal rings of itself every ninth night. For the third and final piece, iron for a hammer, Loki bit Brokkr on the eyelid, so savagely that blood ran into his eyes; this time the smith flinched and swept a hand up to clear his sight, losing his grip on the bellows for one crucial instant. The hammer came out perfect in every respect but one: its handle was shorter than it should have been.

Judging Mjölnir

The finished treasures went before an assembly of the gods — Odin, Thor, and Freyr sitting as judges — with the sons of Ivaldi's gifts set against Sindri's. Odin received Gungnir and Draupnir; Freyr received Skíðblaðnir and Gullinbursti; but it was the last item, the short-handled hammer, that decided the contest. The gods ruled that Mjölnir — a weapon that could strike any target, never fail, and always return to the hand that threw it, capable of guarding the gods themselves against every jötunn who might come against them — outweighed every other treasure on the table, short handle and all, because it alone answered the gods' one standing fear: an attack from Jötunheim they could not repel. Sindri and Brokkr were declared the winners of the wager.

The debt collected

Having lost, Loki tried to buy his way out on a technicality, offering the dwarves gold in place of his head; when Brokkr refused any substitute, Loki fled the scene entirely, using a pair of shoes that let him run across both air and water. Thor was sent to run him down and dragged him back for sentence. Loki then produced his cleverest escape yet: the wager, he pointed out, was for his head — and Brokkr had no claim whatsoever to his neck. No blow could be struck without touching the neck to reach the head, so the letter of the bargain protected him entirely. Furious but outmaneuvered, Brokkr settled for the only penalty the deal still allowed: he took an awl and a thong called Vartari and sewed Loki's lips shut, silencing the trickster, at least for a while, by the very cunning he had just used to save himself.

In the primary sources

The entire episode survives in one place: Skáldskaparmál, in Snorri's Prose Edda, told as the origin story explaining why gold can be called "Sif's hair" in skaldic kennings, and, along the way, why the gods possess their greatest treasures at all. No Eddic poem narrates the wager directly, though the treasures it produces — Gungnir, Draupnir, and above all Mjölnir — are named throughout the Poetic Edda as simple facts of the gods' arsenal, their manufacture assumed rather than retold.