She spends a long time with her sisters as prisoners of Gorr the God-Killer, who uses them as slave-labor to build a God-Bomb. When the trio realize said bomb would kill all Gods in space and time, they lead a rebellion, which includes three versions of their beloved Grand-father. The current (to them) one, an adult version, pre-Odin-power, and a young one before he gained the might of Mjolnir. Gorr is defeated with, with fatalities from Ellisiv's side.
Later, during a much more peaceful time at Asgard, Ellisiv and her sisters realize Thor is neglecting his duties to attend to the ruined shell of Earth/Midgard. So they decide to do something about i.