Lucia originally arrived on Earth alongside Radia. When Radia dies, Lucia swears she will kill the Gransazers. Despite Logia ordering her not to fight them just yet, she attacks Samura and fights Tenma and Gou. She later gets scarred by Ai and attempts to get revenge on her, but is stopped Ran and Mika arrive and help Ai defeat Lucia. She is then taken to a hospital in order to heal her, but human medicine has no effect on her. However, she is rescued by Logia.
Despite being ordered not to continue the mission, she attempts to defeat the Gransazers by using Accelerator to increase her power and enlarge her. At first she over-powers the Chouseishin but is eventually defeated by DaiSazer. Despite DaiSazer's pilots making sure not to kill her, she dies as a side affect of the Accelerator's power.