A Honkai (series) character, appearing in Honkai Impact 3rd and Benghuai Xueyuan. She is a clone of Kallen Kaslana made by Otto Apocalypse, dubbed as A-310, in an attempt to bring Kallen back. As a test body, A-310 has excellent Houkai resistance and strong powers. She was born on March 28, 1972. In the world of Honkai Impact 3rd, she was made using the genes of the Honkai Beast Vishnu alongside Kallen's DNA.
Being part of the A Series clones, A-310 did not know her identity and Otto told her that he would tell her anything she needed if she completed the tests. At the final test, A-310 was told by Otto to defeat and kill A-303. A-310 defeated A-303, but refused to kill the other clone. As a result, Otto believed that A-310 could potentially be Kallen's reincarnation due to the empathy she showed, along with her incredible combat capabilities. However, he stated that science is different from reincarnation. Otto would later adopt A-310 and call her Theresa.
Otto later gave the 11th Divine Key, Oath of Judah to Theresa.
