With Marvel Comics' crossover Devil's Reign recently wrapping up, fans of the books are clamoring for more Marvel Universe spanning action. Though they are somewhat commonplace today, crossover events were a rare treat in the past, and the fandom was treated to some of the best ever in the early days.
From the beloved Marvel Super Heroes Secret Wars event, to the classic Kree-Skrull War storyline, the first 10 crossovers set the stage for all future event comics to follow. While other major storylines took place at the same time, only a select few had Marvel heroes crossing over into other books for epic battles and amazing team-ups.
Wraith War
Mostly told across the issues Marvel's Rom series, the Wraith War storyline had global implications for earth, and galactic implications for the Wraiths. After a Wraith invasion of earth is thwarted by Rom and a Skrull execution squad, a second wave of attacks plagues nearly every nation on the planet.
Because of the global implications of the story, it didn't take long for X-Men helped out as well. Beneath the surface of the story is a moral tale about lethal force, and it drew strong lines between heroes who were for and against killing the Wraiths. Unfortunately, it was very Rom centric, and even recognizable heroes couldn't make him an interesting character.
Kree-Skrull War
Claiming the distinction as Marvel's first ever crossover event, the Kree-Skrull War saw The Avengers and company traversing the galaxy. When Captain Marvel is freed from the negative zone, he flees from The Avengers only to stumble his way into an intergalactic conflict between his race and the shapeshifting Skrull.
Generally considered one of the best Avengers comic storylines, the arc brought the interstellar world of Captain Marvel to the usually terrestrial hero team. The story also made strong references to history, and drew parallels between the persecution of superheroes with the persecution of supposed Communists by Senator Joseph McCarthy in the 1950s.
Contest Of Champions
Taking place in its own miniseries book, Contest of Champions contrived a simple reason to bring the Marvel heroes together. To settle a score between two strange deities, each assembles a team of Marvel heroes who are sent out with the goal of collecting all of the pieces of the Golden Globe of Life.
Though it was cheesy, the Contest of Champions was the first time that readers got to see all of their favorite characters together in one book. With Iron Man each leading their own teams, the short series was an omen for the future battles those two heroes would have.
Evolutionary War
By the late 1980s, Marvel had gotten the hang of the crossover story, and the Evolutionary War smoothly branched out across the comics universe. After surviving his encounter with the Hulk, the High Evolutionary decides to purify the human race in order to facilitate a faster evolution for humanity.
Building off of the ideas established in some of Spider-Man. Even villains worked to stop the High Evolutionary, and the cast list was the largest that fans of the books had seen in a crossover up to that point.
Mutant Massacre
The Mutant Massacre storyline wasn't the biggest crossover in Marvel history, but it still managed to tell one of its most compelling stories. The evil Marauders attack a settlement of Morlocks in an attempt to wipe out the entire race. When X-Factor and the X-Men both arrive to stop them, the teams accidentally work against one another.
The only thing that truly makes the event a crossover is the appearance of the best X-Men villains of all time.
Secret Wars II
After the smashing success of Marvel Super Heroes Secret Wars, the followup sought to further explore the character of the Beyonder. Returning to earth to gain enlightenment about humans, the Beyonder attempts to integrate into the world while still maintaining his god-like powers.
The book goes a long way to explain the events of the first Secret Wars and it makes the Beyonder a much more interesting adversary. Once again bringing most of the Marvel Universe together, it takes the concerted effort of superheroes and deities alike to stop him. The story was published across different book series, and was the first time that readers would have to explore most of the Marvel library to get the full story.
Avengers-Defenders War
Most of Marvel's early crossover events were all wars of some kind, and the Avengers-Defenders War represented an epic clash. Marvel's two mightiest teams collide when they fight over possession of the Evil Eye. Soon they learn that they were merely pawns for Loki, and work together to stop the trickster god.
The Defenders have always existed in the shadow of The Avengers, but the battle showed that the team was nevertheless powerful. The real beauty of the arc is that an epic battle turns into an amazing team-up that puts Marvel's two toughest rosters together into an all-star team. With Loki added in to spice things up, the dream team also has a perfect villain to go up against.
Fall Of The Mutants
Tying its story back to the famous Days of Future Past arc, the Fall of the Mutants storyline set in place one of the integral aspects of X-Men lore. As anti-mutant sentiment begins to rise around the country, a rogue politician proposes a mutant registry which forces all mutants to make themselves known to the government.
The story wasn't necessarily linear, and was told across several X-Men titles which each had their own arcs. The chaos of the event led to mutants spilling into other books and hence it became a huge crossover for the Marvel Universe. The arc was dark and political, and was the best that Chris Claremont had to offer during his time at Marvel.
Thanos War
While the Thanos as one of Marvel's best villains, the Thanos War arc actually introduced the big purple heel to the Marvel Universe. The mad Titan Thanos does battle with Captain Marvel and other heroes over possession of the Cosmic Cube.
While it may be tame compared to his universe shattering actions that came later, the Thanos War was still a perfect introduction to the character and his all-consuming motives. Captain Marvel is eventually ed by Adam Warlock, and the pair enlist the help of The Avengers to finally deter Thanos. Though it is only the first chapter, the Thanos War started his saga off with a bang.
Marvel Super Heroes Secret Wars
Revolutionizing comics forever, Marvel Super Heroes Secret Wars capitalized on the success of previous crossovers to make an epic storyline involving most of the Marvel Universe. An entity known as the Beyonder takes an interest in earth and decides to pit its heroes and villains against each other on Battleworld, a mysterious planet designed only for fighting.
Told in its own series, Secret Wars gave readers a fascinating array of combinations of some of their favorite heroes and villains. On top of its exciting story, the arc also featured the first appearance of Spider-Man's black costume which would become integral to his own comics later on. Other arcs may have told better stories, but Secret Wars blazed a trail that permanently altered the future of comics.