In the aftermath of Blackest Night, Lex has found himself tainted by his brief possession of the Orange Ring, and the greed has yet to leave him. Though while one would expect him to be seeking the return of his Orange Ring, Lex is instead in search of a Black Ring, or enough remnants of one to create a new one for himself.
His ultimate goal? To have rings of every color and to rule them all.
So very Lex.