The team encountered new characters such as Arkon in issue #75 (April 1970), and Red Wolf in #80 (Sept. 1970). The team’s adventures increased in scope as the team crossed into an alternate dimension and battled the Squadron Supreme, and fought in the Kree-Skrull War, an epic battle between the alien Kree and Skrull races and guest-starred the Kree hero, Captain Marvel. The Avengers briefly disband when Skrulls impersonating Captain America, Thor, and Iron Man used their authority as founders of the team and disbanded it. The true founding Avengers, minus the Wasp, reformed the team in response after complaints from Jarvis.
Mantis joined the team along with the reformed Swordsman. “The Avengers-Defenders Clash” storyline crossed over between the two team titles. “The Celestial Madonna” arc linked Mantis’ origins to the very beginnings of the Kree-Skrull conflict in a time-spanning adventure involving Kang the Conqueror, and Immortus, who were past and future versions of each other. Mantis was revealed to be the Celestial Madonna, who was destined to give birth to a being that would save the universe. It was revealed that the Vision’s body had only been appropriated, and not created by Ultron, and that it originally belonged to the 1940s Human Torch. With his origins clear to him, the Vision proposed to the Scarlet Witch. The “Celestial Madonna” saga ended with their wedding, presided over by Immortus. The Beast and Moondragon joined the team soon after. A seven-part story featured the Squadron Supreme and the Serpent Crown.
Other classic storylines included “The Bride of Ultron“, the “Nefaria Trilogy”, and “The Korvac Saga”, which featured nearly every Avenger who joined the team up to that point. Henry Peter Gyrich became the Avengers’ liaison to the United States National Security Council. Gyrich was prejudiced against superhumans and acted in a heavy-handed, obstructive manner, and insisted that the Avengers followed government rules and regulations or else lose their priority status with the government. Among Gyrich’s demands was that the active roster be trimmed down to only seven members, and that the Falcon, an African American, be admitted to the team to comply with affirmative action laws. This last act was resented by Hawkeye, who because of the seven-member limit lost his membership slot to the Falcon. The Falcon, in turn, was unhappy to be the beneficiary of what he perceived to be tokenism, and decided to resign from the team, after which Wonder Man rejoined. The true origins of Quicksilver and the Scarlet Witch were revealed in a three-part story that ran in issues #185-187 (July-Sept. 1979). After this adventure, the Scarlet Witch took a leave of absence and Ms. Marvel officially joined the team as her replacement.