Serra

Serra was a human female planeswalker, named after Goddess Serra, who created her own heavenly plane, Serra's Realm, formed purely with white mana and populated by her famous Serra Angels as well as human worshippers. This paradise came to an end when Urza Planeswalker appeared, wounded from an attack on Phyrexia. He spent years there recovering and left in peace, but the Phyrexians attacked shortly thereafter, killing many of Serra's subjects. Worse, the black mana essence of the Phyrexians tainted Serra's Realm, so that Serra herself could no longer stand to stay there.

She wandered the planes for some time afterward, eventually meeting and falling in love with another planeswalker named Feroz. They lived together on the plane of Ulgrotha for some time, protected from the rest of the multiverse by Feroz's Ban, and protecting the people of Ulgrotha from Baron Sengir and his vampires. That is, until Feroz himself was killed. Serra, heartbroken, joined him in death soon after when she was surprised by a thief who was a disguised planeswalker.

More recently, J. Robert King's novel Scourge said that Serra and her realm had been returned to existence after the destruction of the Weatherlight released the captured plane, which had served as a power source for the skyship. Though Serra's death is prerevisionist and Scourge is much more recent, the continuity of the novel is dubious in many respects, leaving Serra's status questionable.