The Collector becomes an important pawn to the Brethren, particularly after a discovery in one of his ecosystems. Who is Olar, the strange creature who claims to be “the eldest of the Brethren”?

The Collection Obession Part 5 of 6. (Note-Cover states this is part 4 of the story, but this is actually part 5)

The group of Black Panther, Quasar, Beast, and the Collector take a moment to bury a tribe member, Nakka, who helped them find the Brethren's home world. Just as they finish something emerges from beneath the grave, a creature named Olar, who claims to be the oldest of the Brethren, left there to die. Olar returns to Earth with the Avengers, but is quickly killed before he can reveal the secrets of the Brethren. Thane Ector, upon learning that the Collector is with the Avengers moves to attack them and destroy both the Avengers and their great opressor, the Collector. Thane makes his way through the Avengers, and finally gets his hands on the Collector, but suddenly an explosion sends everyone staggering. When everything clears the true form of the Collector is finally revealed, as is his plan to destroy the human race.