Irish:
Caladbolg -("hard belly", or possibly "hard lightning"), sometimes written Caladcholg ("hard blade"), is the sword of Fergus mac Róich from the Ulster Cycle of Irish mythology. Spelled Caladcholg, it is also associated with the more obscure Ulster hero Fergus mac Leda, suggesting a conflation of two legends. It was said to be a two-handed sword that made a circle like an arc of rainbow when swung, and to have the power to slice the tops off hills and take out an entire host. During the Táin Bó Cuailnge, Ailill mac Máta takes Caladbolg away from Fergus mac Róich when he discovers Fergus' affair with his wife Medb. He gives it back when the Ulstermen rally against his armies. Fergus wreaks havoc against Ulster's forces with his blade, but Conall Cernach convinces him not to kill Conchobar mac Nessa. Fergus strikes the Three Great Strokes on three small hills instead, blasting off their tops.
ClaÃomh Solais – Sword of Nuada the king of the gods in Irish mythology; In legend, the sword glowed with the light of the sun and was irresistible in battle, having the power to cut his enemies in half.
Gáe Bulg (also Gáe Bulga, Gáe Bolg, Gáe Bolga, , meaning "notched spear", "belly spear", "swelling spear", "bellows-dart", or possibly "lightning spear", was the spear of Cúchulainn in the Ulster Cycle of Irish mythology. It was given to him by his martial arts teacher, the warrior woman Scáthach, and its technique was taught only to him.
It was made from the bone of a sea monster, the Coinchenn, that had died while fighting another sea monster, the Curruid. Although some sources make it out to be simply a particularly deadly spear, others—notably the Book of Leinster—state that it could only be used under very specialized, ritual conditions:
“ The Gáe Bulg had to be made ready for use on a stream and cast from the fork of the toes. It entered a man's body with a single wound, like a javelin, then opened into thirty barbs. Only by cutting away the flesh could it be taken from that man's body.[1] ”
In other versions of the legend, the spear had seven heads, each with seven barbs. In the Táin Bó Cuailnge, Cúchulainn received the spear after training with the great warrior master Scáthach in Alba. She taught him and his foster-brother, Ferdiad, everything the same, except she only taught the Gáe Bulg feat to Cuchulainn. He later used it in single combat against Ferdiad. They were fighting in a ford, and Ferdiad had the upper hand; Cúchulainn's charioteer, Láeg, floated the Gáe Bulg down the stream to his master, who cast it into Ferdiad's body, piercing the warrior's armor and "coursing through the highways and byways of his body so that every single joint filled with barbs." Needless to say, Ferdiad died soon after. On a separate occasion, Cúchulainn also killed his own son, Connla, with the spear. In both instances, it was used a last resort, as once thrown it proved invariably fatal.
Fragarach, known as 'The Answerer' or 'The Retaliator', was the sword of Manannan mac Lir and Lugh Lamfada.
Forged by the gods, Manannan wielded it as his weapon before passing it on to Lugh (his foster son). It was given to Cúchulainn by Lugh, and later to Conn of the Hundred Battles.
It was said that no one could tell a lie with Fragarach at his or her throat, thus the name 'Answerer'. It was also said to place the wind at the user's command and could cut through any shield or wall.
MOAR NORSE WEAPONS!
Gungnir (Old Norse "swaying one") is Odin's magical spear, it always hits its mark and always kills.
Dáinsleif ("Dáinn's legacy") is king Högni's sword, according to Snorri Sturluson's account of the battle known as the HjaðningavÃg.
Lævateinn is a weapon mentioned in the Poetic Edda poem Fjölsvinnsmál. The name Lævateinn does not appear in the original manuscript reading, but is an emendation from Hævateinn made by Sophus Bugge and others. The amended name Lævateinn is etymologically considered to be a kenning for a sword (Old Norse "damage twig").
Gram (Old Norse "wrath") is the name of the sword that Sigurd (Siegfried) used to kill the dragon Fafnir. It was forged by Wayland the Smith and originally belonged to his father, Sigmund, who received it in the hall of the Volsung after pulling it out of the tree Barnstokk into which Odin had stuck it—no-one else could pull it out. The sword was destroyed and reforged at least once. After it was reforged, it could cleave an anvil in twain.
In the Nibelungenlied, Siegfried's sword is called Balmung; in Richard Wagner's Ring Cycle, it is called Nothung.