The fire giant of Muspelheim, burner of the world
The gatekeeper of the fire-realm Muspelheim, wielding a sword of flame brighter than the sun. Since the world’s beginning he has stood at its southern border, awaiting the end. On the day of Ragnarök he will lead the host of fire giants across the rainbow bridge, slay the fertility god Freyr, and swing his sword to set the nine worlds ablaze — the old world turns to ash in his flame, clearing the way for the birth of the new.
When the horn of Ragnarök sounds, Surtr drives in from the south, and beneath his feet the rainbow bridge collapses. He cuts down the swordless Freyr, then scatters the flame of his fiery sword across heaven and earth — the land sinks into the sea, the stars fall, and gods and giants perish together. Only after the embers cool will a new earth rise from the sea.
Below are how modern works borrow or reinterpret this name or story — not the original material. The two differ, so keep them apart.