The Contessa is Lex Luthor's ex-wife, the mother to Lena Luthor, and the leader of the Agenda. She is an immortal who is, at least, older than 210 years old.

Contessa Erica Alexandra Del Portenza

The Contessa is Lex Luthor's ex-wife, the mother to Lena Luthor, and the leader of the Agenda. She is an immortal who is, at least, older than 210 years old.

All data from the awesome folks at Marvel.