Dr. Jane Foster is a physician[14] who empowers herself as the mighty goddess of thunder Thor when wielding Mjolnir[15] or as the deathly Valkyrie when wearing the Undrjarn the All-Weapon.[1] Foster has become entangled with the adventures of the Norse god of thunder Thor on Earth for working in the past as a nurse for his human alter-ego Donald Blake.[16] Deeply infatuated with the divine hero, for years her life was influenced on many levels by his actions.[17][18] Tragedy was inflicted upon Foster when her ex-husband and son died in a car accident[19] and she contracted breast cancer. This drastically changed Foster's views on worshipped deities and also brought her close to Thor again.[20] After Thor lost the worthiness of communing with Mjolnir, the magic hammer that provided him thunder powers,[21] Foster was able to wield it, ascending as a new worthy Thor who had the experience of being an earthly hero. However, being Thor caused her to neglect her treatment against cancer as she effectively sacrificed her health to save others.[15] For months, she secretly operated as a competent champion in the Ten Realms, earning the respect and gratitude of many and the hatred of ignoble villains.[22] Her tenure as Thor came to an end after she gave up on Mjolnir to end the beast Mangog.[23] No longer a Thor, Foster had her cancer enter into remission.[24] She came back to action when the dark elf Malekith moved his vile troops to invade Earth, as she protected it both politically and as a warrior, momentarily empowering herself as Thor to fight the villain using fragments of a Mjolnir from a different universe.[25] The fragments reshaped themselves as a versatile weapon, and Foster took up on the legacy of the name Valkyrie following the demise of the Asgardian Valkyries during Malekith's invasion.[1]