What does Thor primarily use Mjolnir to fight?

The story behind the answer

Giants. In Norse myth, Thor is the gods’ protector, and his hammer Mjolnir is chiefly wielded against the jötnar (giants), chaotic forces that threaten gods and humans alike. Many of Thor’s famous adventures—defeating Hrungnir, battling Geirröd, and reclaiming his stolen hammer from the giant Thrym—center on smashing giants back into line. Even Jörmungandr, the World Serpent, belongs to the giant-kind.

Remember it this way: Thor thunders; giants are his thunder’s target. Mjolnir isn’t just a weapon—it returns to his hand, channels lightning, and even sanctifies weddings and oaths. But when trouble looms on Midgard’s borders, it’s the giants who feel the hammer’s bite first.