The Soulbreaker was originally forged to house the power of the Lost Souls, demonic parasitic creatures that gave birth to the being known as Angrir, the Breaker of Souls. Angrir was freed from his prison by the Serpent, Cul and joined his Worthy. Following the defeat of the Cul, Angrir and the rest of the Worthy were imprisoned in their hammers and hidden in the dark corners of Asgard until the Serpent was freed by his daughter centuries later.
The Soulbreaker was freed and landed on Yancy Street where the Future Foundation sought out the hammer and it took possession of the Thing, making him the new Angrir. As Angrir, the Thing destroyed the rest of Yancy Street and then later beat down both the Red Hulk and destroyed Avengers Tower. Angrir and Nul, the Breaker of Worlds were sent to stop Thor, but Thor fatally wounded Angrir allowing the Thing's persona to come back in. At death's door, Franklin Richards used his powers to reverse and heal the Thing and reimprisoned Angrir back in his hammer.
The Soulbreaker currently remains in the Baxter Building, but is being sought after Valkyrie, but the Thing will not allow the hammer to do any more death and destruction like it once did. After a brief tussle, Valkyrie explained the true powers of the various hammers and why she needed to find them and return them to Asgard. It was then that the Thing realized that she was right and let her take the Soulbreaker into her possession.