If you're inspired by the Avengers movies to read more about Thanos, here's a guide to some great collections. (Spoilers ahead.)
This is the big one, the 1990-91 miniseries adapted in "Avengers: Infinity War," where Thanos gets all the Infinity Gems and wipes out half the universe with a snap of his fingers. The scale is even larger, and the fate of the Avengers is shocking (until the inevitable third-act reversal, of course). This series gives Thanos a different reason to wipe out half of all life than the movie — to impress his girlfriend, the personification of Death. Also: Adam Warlock, Silver Surfer and the cosmic entities of the Marvel Universe do big, cosmic things. Rating: Six Gems.
In this 2002 story, because of a problem in the timeline in "Avengers Forever," Atleza, the Anchor of our Reality, has arrived too late to be trained by her predecessor, and must be protected and educated by Adam Warlock and Gamora. (The former has been driven insane by the knowledge necessary to train a Reality Anchor, and the latter is an assassin ill-suited to babysitting.) Elsewhere, Thanos has been split into five doppelgängers, each representing one aspect of his personality, all of which have reverted to the nihilism of his early days, and are searching for Atleza to use her power to kill half the universe again. How can you not want to read this story? Rating: Five Gems.
Even monsters have to start somewhere, and this collected miniseries gives us Thanos' birth, childhood and early schooling. What happens? Hint: Things don't go so well for the Mad Titan's parents and schoolmates. Rating: Four Gems.
'Thanos Wins' TPB
What happens if Thanos wins? We find out when a future Thanos sends the Cosmic Ghost Rider (formerly Frank Castle) to kidnap the present-day Thanos back to the apocalyptic future where older Thanos has killed almost everyone — and is ready to join his victims (with Death), at the hands of his younger self. But present-day Thanos calls shenanigans and the Thanos vs. Thanos cage match begins. Also: We learn Thanos' birth name! Rating: Four Gems.
'Marvel Universe: The End' HC
But wait! "Thanos Wins" isn't the first time we've seen Thanos do that voodoo he does so well. In 2010, Marvel published a bunch of stories that depicted possible demises for its main characters. And in one spasm of nihilism, the publisher wiped out everything in the six-issue series "Marvel Universe: The End." But, weirdly, this one series was actually "in continuity," as we comic fans say, meaning it "counts." And guess who wiped out the universe — and then brought it back? Yeah, that purple guy again. But it wasn't just an exercise in pessimism; the series had a point. There comes a time when Thanos is sitting in a white void, having destroyed everything, as he does. And in that void, he is joined by, um, let's say a friend — who teaches Thanos the surprising reason for his existence. Rating: Five Gems.