Warning: The following contains spoilers for Justice League #34 by Scott Snyder, James Tynion IV, Howard Porter, Bruno Redondo and Hi-Fi Color Design, on sale now.

Across a number of DC titles over the last month, the mysterious green symbol has appeared in the sky. The symbol has appeared in the pages of disparate titles like Justice League Dark, Supergirl, Batman, Wonder Woman, The Flash, Hawkman and more. While its appearance is sudden and largely unexplained in those titles, the Doom Signal has a deep connection to the most recent events of Justice League, which have seen the basic structure of the multiverse is about to be radically changed.

As The Flash #81 suggests the Signal is a portent of something messing with time and space, meaning the symbol could be appearing to people all around the world at different moments in the modern DC continuity. While it doesn't appear in every comic DC has released over the past few weeks, namely in titles that tie-in to DC's Year of the Villain event. (Ironically, Harley Quinn even sees it and decides to try and kill the concept of crossovers themselves to prevent whatever nasty events are associated with it.) Now, we're taking a closer look at what the symbol means, and how it could spell certain doom for DC's heroes.

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The Coming Of Petpertua

The Doom Signal bears a striking resembelance to the classic headquarters of the Legion of Doom, who've recently been engaged in an ongoing struggle against the Justice League. After the Source Wall was cracked following the events of DC Metal, the four Omega Titans were introduced to the greater DC Universe. The Justice League sprang into action to fight them, but their actions also led Lex Luthor to come to the ultimate conclusion that for life to flourish, doom must truly triumph over justice. He recruits a new Legion of Doom to help him take control of the Totality, a reality-altering artifact that's essentially DC's equivalent to Marvel's Cosmic Cube, that has a link to Perpetua.

As the mother of cosmic beings like the Monitor, the Anti-Monitor and the World-Forger, Perpetua has been sealed away for millennia and unable to interact with the multiverse her dark hand helped create. Luthor has become her biggest prophet, and her release into the universe could have dire consequences for the forces of good. The Doom Signal is also fundamentally connected to her and her influence, and it's spread by more people giving in to the ideals of fatalism and doom.

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To that end, Luthor and his cohorts have gone to war against the Justice League. Luthor has even sacrificed his human body to take on a new one (that's been forcibly fused with the body of Martian Manhunter,) blessing Luthor with incredible powers so that he may better serve her.

On a similar note, this was also the motivation behind Luthor traveling around the world and offering villains new advantages and powers in exchange for preaching the gospel of doom. All of this tipped the scales of the galaxy, as the more people who believe in his fatalistic teachings got Lex closer and closer to being able to free his new goddess.

In Justice League #34, Luthor is able to free her from her prison and set her against the multiverse once more, allowing her to tip the scales in favor of doom. This is what led to her symbol appearing in the sky across so many of DC's titles. It's also why several instances of its appearance coincide with villains seemingly emerging from moments of triumph.

The fallout of Petpetua's freedom and the Doom Signal will continued to be explored in Justice League #35, which is set to be released on Nov. 6.

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