Magni

Magni is a son of the thunder god Thor and the giantess Jarnsaxa, and one of the few gods who survive Ragnarok and inherit Thor's hammer Mjolnir. His name means “strength”, and at three nights old he lifts a weight that none of the other gods could move.

His great scene comes in Skaldskaparmal, in Snorri Sturluson's Prose Edda. Thor kills the stone-headed giant Hrungnir in a duel, but a piece of the giant's whetstone strikes his head and fells him, and Hrungnir collapses on top of him with a leg across Thor's neck. Thor's servant Thjalfi cannot lift it, and neither can all the Aesir together. Then Magni arrives, three nights old, throws the leg off his father and says it is a shame he came so late, for he would have struck the giant dead with his fist. Thor gets up, welcomes his son, says he will grow up to be mighty and gives him Hrungnir's horse Gullfaxi. Odin protests that Thor should not give so fine a horse to the son of a giantess rather than to his own father.

The rest of his story belongs to the end of the world. Vafthrudnismal says that Modi and Magni will have Mjolnir when Thor's fighting is over, and Snorri repeats it in Gylfaginning: Thor dies from the venom of the World Serpent Jormungandr, a green new earth rises from the sea, Vidar and Vali live at Idavoll where Asgard once stood, and Thor's sons Modi and Magni join them with the hammer, followed by Baldur and Hodur returning from Hel.

In Harbardsljod Thor introduces himself as “Magni's father”, and in Snorri's kennings Thor is the father of Magni, Modi and Thrud, while Sif is “Jarnsaxa's rival”, the only hint of what bound Thor to the giantess. Nothing else is told of Magni: not whether Modi shares his mother, nor what he does in the new world. No source calls him the strongest of the gods either; Snorri gives that title to Thor, and Magni's fame rests on the scene with Hrungnir's leg.