Young Justice #18 contains a great many spoilers about Spoiler (Stephanie Brown), and not just about who has been trying to kill her, but what really happened to Steph’s criminal father, Cluemaster, in "Batman Eternal" and what the future of Drake (Tim Drake)’s name will be. (This is relevant since Spoiler is Drake’s girlfriend after all.) Turns out, Cluemaster sent his goons after his own daughter with the goal of killing her, since she has been rather relentless in her efforts to stop his criminal enterprise.
In a flashback, Drake learns how tenacious Spoiler really is after she reveals how her search for Cluemaster led to Central City. There, Steph not only had to contend with another criminal named La Tombe who just so happened to be hunting her father down as well, but doing so while trying to prevent La Tombe from killing her father’s goons as they tried to kill her on her father’s orders.
While this might make Cluemaster seem rather heartless (and he is), this isn’t to say he didn’t try to get Steph off his trail so he wouldn’t have to kill his own daughter. In fact, Cluemaster reveals that he faked his own death in "Batman Eternal" so she would stop looking for him. But as he says, “I tried to make it easy for her. I’m dead and she’s still looking for me. Why?” (Spoiler answers this later in the issue when she tells Cluemaster that she wants him to put down his weapons, turn himself in, pay his debt to society, and go to family counseling with her and her mom.)
In his own twisted way, Cluemaster also thinks he was doing the right thing by having other people kill Steph instead of him. When his men try to give him advice on how to deal with Spoiler, Cluemaster gets frustrated by what they are implying when he says incredulously, “So I should kill my own daughter? With my bare hands?” Incredibly, he even expects his daughter to give him credit for trying not to kill her and almost becomes irritated when she refuses to do so.
By the end of the issue, yet another spoiler is uncovered, which is that Cluemaster is not really that much of a threat. During the final “battle,” Cluemaster fails to land any attacks on either Drake or Spoiler. Meanwhile, he gets caught in an explosion from Drake’s exploding Batarang while Spoiler kicks him in the face, in the gut, and then snap kicks him in the jaw. That’s before the Young Justice team suddenly arrives on the scene and stops Spoiler before she has a chance to land the finishing blow. In just one cell, Teen Lantern creates a cage from the green light of willpower of the Emotional Electromagnetic Spectrum and traps Cluemaster inside it almost immediately.
There's one other major spoiler as well. Drake reveals that he is going back to being called Robin. Finally!