The team is gathered at the mansion, and Captain Marvel, Moondragon and Adam Warlock pay a visit. They discover that Thanos has united the Soul Gems, and created a star-destroyer cannon with them. His armada shows up at the edge of the solar system, the Avengers board the main ship and defeat all the weird aliens in it. But Thanos is not there, he's at another ship, at the other side of the solar system. Warlock and Marvel leave the fight to get him, and Thor and Iron Man follow them. Thanos kills Warlock and defeats Marvel, but Iron Man destroyed his big weapon. Thanos returns to the other ship, easily defeats and captures the Avengers, and gets a new plan: use Warlock's gem to destroy the sun.
Moondragon sent a psychic SOS received by Spider-Man, who asked the Thing to lend him a ship there. They were defeated as well, but Spider-Man managed to free the Avengers. A new fight started, and Spider-Man managed to break the Soul Gem: Adam Warlock returned to life, turned Thanos into stone, and then died again.
This story provides examples of...
- Avengers, Assemble!: We see all of the Avengers' thoughts about the upcoming battle as they to fight Thanos' armada.
- Because Destiny Says So: Captain Marvel and Moondragon show up at Avengers Mansion simply because they felt that their powers would be needed that night.
- Curb-Stomp Battle: Thanos defeated Adam Warlock with just a pair of swift movements. He pointed himself that he wouldn't have expected that it would be so easy to defeat The Chosen One.
- Doing In the Wizard: Once he had all the Soul Gems, Thanos built a machine to harness their power.
- The Dreaded
- There is only one person in the entire universe that Thanos fears: Adam Warlock.
- And of course, Thanos himself.
- Even Evil Has Standards: Gamora had been a faithful servant of Thanos, but when she discovered that he intended to commit stellar genocide, she tried to kill him. Thanos noticed it and killed her.
- Foreshadowing: First one is some time before this story, at Warlock #11. Trying to prevent himself from turning into the Magus, Warlock (with Thanos' help) uses a time probe to go some months into the future. He finds his future self in some destroyed sci-fi setting, dying among the remains. The dying Warlock is fully aware of what is his younger self about to do: capture his soul with the Soul Gem. He is completely bitter and cynical, and ready to die. "Short time? You fool, it's been an eternity. During that time, everything I've ever cared for or accomplished has fallen into ruin! Everyone I've ever loved now lies dead! My life has been a failure! I welcome it's end!◊" Warlock captures his future self's soul, and returns to the present. Time passes. In this story, Thanos revealed that he was Evil All Along and the Avengers, Warlock and Captain Marvel fought against his armada. His main ship was actually a decoy, so Warlock and Marvel left the Avengers and fought Thanos at his real ship. And, after the battle... exactly the same thing happened◊.
- Fully Absorbed Finale: This story and "The Death of Captain Marvel" killed all of Marvel's cast of galactic characters in the late 1970s, as Marvel intended to focus on more realistic characters from then on.
- Hidden Agenda Villain: The villain Thanos had once joined forces with Adam Warlock against the Magus. Enemy Mine? No, Thanos had his own reasons for doing so, detailed here.
- Lost Common Knowledge: Thanos discovered the Soul Gems in a scroll from a dead world.
- Motive Decay: In the beginning of the story, Thanos intended to destroy all the stars of the universe. By the end, he would settle just with destroying our sun.
- My Significance Sense Is Tingling: When Thanos destroyed the first star, Moondragon felt the disturbance in the force.
- Red Eyes, Take Warning: Pip thought that Thanos was his pal. His eyes glowed when he explained that he once had an agenda that made him work with Warlock, and in turn be civil with Pip; but now things have changed.
- Right Behind Me: Pip was manifesting his relief that Thanos was absent, when Thanos emerged from the shadows and grabbed him.
- Stealth Hi/Bye: Warlock goes to ask the Avengers for help, but he's suddenly missing after the report by Starcore, and goes to deal with Thanos himself.
- Taken for Granite: Pip the troll was turned into stone by Thanos. At the end of the story, so was Thanos himself.
- Trap Is the Only Option: Marvel suspected that the fight was too easy, that it had to be a trap. Yet, once caught in the action, the only way out was to play the trap to its full and storm into Thanos' main room.
- You Are Too Late: Adam Warlock flies to a distant planet to fight Thanos, but it is too late. He has already killed Gamora and left.
- Your Princess Is in Another Castle!: Thanos is not at the main ship at the center of his armada. That's just a decoy. He's actually at a lone ship at the other side of the solar system.