The history of DC/Marvel crossovers ranges from teeth-gritted combat to surprisingly effective romances. But one of the earliest Marvel and DC crossovers, some of the most powerful, deadly cosmic forces from both universes came together in a wholly unexpected way, requiring both the X-Men and the Teen Titans to team up in an unexpectedly harrowing adventure.

Now, we're taking a closer look at what happened when Darkseid and the Dark Phoenix teamed up in Uncanny X-Men & The New Teen Titans by Chris Claremont, Walt Simonson, Terry Austin, and Tom Orzechowski and close the dark lord of Apokolips came to destroying the Earth once and for all.

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Darkseid's endless hunt for control over all things has led him across all of creation, including even into the Marvel Universe on one famous occasion. In Uncanny X-Men & The New Teen Titans, this leads him to try and learn more about the powers behind the Source Wall, with Metron becoming a willing guinea pig for his endeavors. Darkseid ultimately comes to the conclusion that the powers of the Phoenix could be the key to deciphering the Source. To that end, he sneaks into the Xavier Institute and draws the knowledge and memories of Jean from the X-Men -- along with locating remnants of her power -- in an attempt to amplify that power and bring about the rebirth of the Dark Phoenix.

Darkseid also recruits Deathstroke who, along with a horde of Parademons, are able to capture both teams while Darkseid continues to draw the remnant Phoenix energy from around the world. Combined with the psychic residue within the X-Men, Darkseid is able to force the Dark Phoenix to resurrect herself. The two cosmic villains are quick to make a pact, with Darkseid intending to use her as the ultimate tool towards spreading his will across the universe. Luckily, the X-Men and Teen Titans are able to quickly form an alliance and chase down the two forces, utilizing Metron's abandoned chair to escape the depths of space where Darkseid left them to die.

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Cyclops possessed by Dark Phoenix Taking On Darkseid

However, the team isn't able to reach them in time before Dark Phoenix unleashes a cosmic blast that will reach the core of the planet Earth and turn it into a new Hellpit from which Darkseid will begin his conquest of the rest of the universe. The villains come incredibly close to succeeding, too. But the teams are at least able to stall them long enough for Raven and Xavier to combine forces and attack Dark Phoenix with the full weight of the X-Men's memories and feelings for her. Robin is able to trick Dark Phoenix into reabsorbing the cosmic blast to sustain herself. With no other options to survive, the Dark Phoenix tries bonding with Cyclops as a physical host, decades before the Phoenix Force bonded with him in Avengers vs. X-Men. However, this is the final key to unlocking Dark Phoenix's full memories and knowledge of the situation.

Overcome by Cyclops and the truth he knows, the Dark Phoenix is forced to accept that she died during the events of "The Dark Phoenix Saga," sacrificing herself to save everyone she cared about and the whole world in the process. Enraged at the fact that her resurrection was only a brief one to serve Darkseid's ambition, the Marvel cosmic force turns against Darkseid and attacks him. Dragging Darkseid back into the cosmos, Dark Phoenix brings him to the Source Wall and traps Darkseid within it, saving the universe.

Still, Darkseid and Dark Phoenix working together is one of the most dangerous prospective alliances of villains possible, two unstoppable and unbreakable sources of chaos and destruction. Luckily, the humanity of Jean Grey that informed the core of the Dark Phoenix proved to be the ultimate way to reach her and save all of creation.

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