WARNING: The following article contains spoilers for Justice League: No Justice #3 by Scott Snyder, James Tynion IV, Josh Williamson, Riley Rossmo and Marcus To, in stores now.
In order to convince the Justice League to save Colu, Superman nemesis Brainiac ensured that if his home planet was destroyed, the Omega Titans, the DC Universe's latest and biggest threat, would target Earth next. Essentially, the villain blackmailed the Justice League into saving the day in Justice League: No Justice.
At the time, it seemed like the only way he could get the Earth's heroes and villains to work together, but there was an ulterior motive at play as well: Brainiac's plan to save Colu was also a plot to enslave it by taking control of the planet's key resources. The villain thought he could use the heroes to trick the Omega Titans into sparing the planet before they went on to destroy Earth once and for all.
Unfortunately for him, Brainiac's plan didn't allow for the possibility of a psychic attack blowing his head up. Without his precision planning, the entire operation fell apart, the heroes were unable to save Colu, and now Earth is next on the menu.
The Cosmic Trees of Earth Rise
Colu is dead. Mere moments after the Wisdom Titan consumed the planet Colu, the seeds on Earth sprang to life. The seed that Waller and Green Arrow have been fighting over has now activated, and four distinct trees grow across the world, each representing one of the four energies of sentient life, just like we saw on Colu. The four trees also grow in specific locations that embody their respective energies.
That means the Earth's Tree of Mystery has sprouted in the Arctic Circle near Superman's Fortress of Solitude. Considering the Man of Steel was recruited onto Team Mystery, it makes sense that his secret headquarters, where many alien artifacts are housed, would embody the power of Mystery. The Tree of Wisdom grows out of a S.T.A.R. Labs building, which is fitting considering the location is home to a lot of learning and information gathering.
The Tree of Wonder rises out of the ground near the Tower of Fate; Dr. Fate's headquarters in Salem, Massachusetts is typically considered to be a nexus of magical energy. The Tree of Entropy matures at Belle Reve Prison, home to the Suicide Squad. Colu's tree was also growing out of a prison, so it seems only natural that the same would happen on Earth. Being the home of incredible chaos makes it the perfect place for this cosmic tree to bloom.