What is the name of the hall of slain warriors in Asgard?

The hall of slain warriors in Asgard is Valhalla.

Valhalla, from Old Norse Valhǫll, is Odin’s great hall in Asgard. Valkyries choose many warriors who die in battle and bring them there, where the fallen are known as the einherjar. They feast, drink, and fight in preparation for the final conflict of Ragnarök, when they are expected to join Odin against the forces of chaos.

The hall is described as vast and magnificent, with a roof associated with shields and doors large enough for enormous numbers of warriors. Its daily cycle of combat and restoration reflects the martial culture emphasized in the surviving Norse heroic tradition.

Valhalla is not the only destination for the battle-dead. The goddess Freyja is said to receive a share of those slain in her field, Fólkvangr. This is why Fólkvangr is sometimes confused with Valhalla, but Valhalla remains the canonical answer when a quiz asks for Odin’s hall of slain warriors.