Why Mjolnir Has Blue Marks & Cracks In Thor: Love & Thunder

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Thor's enchanted hammer Mjolnir is returning in Thor: Love & Thunder, but with a very different appearance. For centuries, Thor believed Mjolnir was the key to his might. It was only in Thor: Ragnarok that he learned this was not the case; rather, the hammer served as a channel for his power. He only learned this truth after Mjolnir was destroyed by Hela, his elder sister, leaving him shaken at the loss.

But the Thor: Love & Thundertrailer confirms Mjolnir is returning — in the hands of Thor's successor. Possession of the hammer grants anyone who is worthy the power of Thor himself, and now it has been claimed by Thor's ex, Jane Foster (played by Natalie Portman). She's shown holding it aloft, with Thor Odinson watching in amazement; although this may not be Foster's first scene as the Mighty Thor, it seems to have been her first encounter with the Odinson. She's masked, which means that — as in the comics — Thor may well have no idea who his successor really is.

Related: Thor: Love & Thunder Trailer Reveals How Big The Guardians' Role Really Is

The once-shattered Mjolnir has changed, however. No longer is the hammer a perfect one; now, its surface is marked by deep cracks showing where the pieces have been put back together, and blue arcs of lightning can be seen shining out of them. The general assumption is that Jane Foster will reforge the Mjolnir broken in Ragnarok, but the visual design of the hammer seems to suggest that may not be the case; rather, it's possible the blue energy itself is what is holding the pieces in place, explaining why the cracks are still visible.

The interesting question, of course, is how Mjolnir is reforged in Thor: Love & Thunder. In the comics, Mjolnir has been destroyed many times —