The Avengers #167

Two powerhouse teams converge in a striking George Pérez and Terry Austin cover that packs an enormous amount of energy into one image — the Avengers (Thor, Iron Man, Beast, Vision, Captain America, and more) charge forward alongside the Guardians of the Galaxy against a star-filled cosmic backdrop. The bold announcement "Behold… The Guardians of the Galaxy!" sets an appropriately grand tone for this January 1978 team-up, with Pérez's dynamic figure work making every hero feel like they're bursting off the page. Written by Jim Shooter and Roger Stern with interior art by Pérez and inker Pablo Marcos, this is the kind of issue that reminds you why Marvel's Bronze Age lineup was so thrilling.