In the early days of the Justice League, Jim Gordon calls Batman to the Gotham City docks where a dead body appears to have been mutilated by a metahuman, possibly Superman. In the decendant's pocket is a green bullet evidently made of Green Kryptonite. Batman searches for clues and ends up calling Superman to his city where the two talk and Superman explains that he has taken a vow to never kill. Batman reveals that the bullet is a very elaborate fake but not true Kryptonite. The duo set out to stop whomever is framing him and find Intergang with some advanced LexCorp body armor in a nearby warehouse that allows humans to mimic several of the Krytonian's powers. Batman pays a visit to Lex Luthor and warns him that the League protects their own.