After years of their movies going up against each other, Marvel and DC Comics are coming together again on the page with a new crossover. At this weeks ComicsPro retailer expo, Marvel and DCs respective editors-in-chief C.B. Cebulski and Marie Javins jointly announced the upcoming event, which they teased would be hitting sometime this year. They didnt show any artwork or announce a creative team, but according to ComicsBeats Heidi MacDonald, this meetup will take the form of two one-shots,Marvel/DCandDC/Marvel. Longtime comics fans will remember how the Big Two were no strangers to hanging out back in the day. This first took the form of various one-shots in the 1970s and 80s pitting Spider-Man against Superman or the Teen Titans vs. the X-Men. In the late 90s there were DC Versus Marveland theAmalgam Agecomics, wherein each publishers respective heroes went up against each other (Batman vs. Captain America or Silver Surfer vs. Green Lantern), sometimes with readers voting on whod win a particular matchup. The Amalgam books fused heroes togetherDark Claw was Wolverine and Batman, Wonder Woman was Storm, etc.in a merged universe later canonized as Earth-9602 for Marvel and Earth-496 for DC. (Or Earth-1996 for both.) In 2003, GeorgePrez and Kurt Busiek collided the worlds again in JLA/Avengers,a comic first approved all the way back in 1979. There, the heroes of Marvel and DC fought to save one anothers worlds instead of their own (or the combined version of them), which led to both teams thinking the other are terrible at protecting their home dimensions. All three of these crossovers have been republished in the last few years likely to help set the foundation for this new union. Well have more on Marvel/DC and DC/Marvel as news develops. Want more io9 news? Check out when to expect the latest Marvel, Star Wars, and Star Trek releases, whats next for the DC Universe on film and TV, and everything you need to know about the future of Doctor Who.