Umbra in The Elder Scrolls IV: Oblivion is a Wood Elf (Bosmer) warrior named Lenwin who resides in the Ayleid ruin of Vindasel, southwest of the Imperial City

. She named herself after the powerful Daedric artifact sword Umbra, which she found at some unknown point in the past. The sword has the ability to trap souls and is known for its jet black color and wicked edge

. Lenwin was originally an apprentice under a warrior named Irroke the Wide at Pell's Gate. After acquiring the sword Umbra, she became increasingly bloodthirsty, driven by the sword's insatiable hunger for souls. She eventually became a mercenary but later retreated to Vindasel, where she now wanders, seemingly regretful and trying to prevent further deaths caused by the sword

. In the game, players encounter Umbra in the final room of the Vindasel ruins. They have the choice to either fight her and claim the sword or leave peacefully. If defeated, Umbra drops the Umbra sword, one of the strongest one-handed swords in Oblivion with a soul-trapping enchantment

. Umbra's story is tied to the Daedric Prince Clavicus Vile, who desires the sword back. The sword and the character Umbra are deeply connected, with the sword influencing her mind and actions

. In summary, Umbra is both a character and a legendary sword in Oblivion, with Lenwin being the warrior who took on the name Umbra after being possessed by the sword's power