"The end is near."
Those are the first words spoken by Thanos in the final trailer for Avengers: Infinity War. After appearing mostly to the background of the Marvel Cinematic Universe, the Mad Titan will finally take center stage as he actively begins his quest to collect all six of the Infinity Stones.
Though moviegoers are likely to not know much about Thanos heading into Avengers 3, fans of the comics should be pretty familiar with the villain's goals and motivations; he wants to destroy all life in the universe in order to gain the favor of his beloved Death. However, as more information continues to be released for Infinity War, the more we learn that MCU Thanos and Marvel Comics Thanos are not one and the same.
While their goals are still very similar (wiping out the universe, or half of it, at least), the reasoning behind MCU Thanos' actions make him a much more sympathetic figure, which will work in his favor going forward.
The Noble Mad Titan
In the comics, Thanos is responsible for the destruction of Titan, the planet he once called home. However, in the MCU, Thanos actually tried to save his planet but was unsuccessful. This failure becomes the catalyst for the chain of events that lead to Infinity War, according to Marvel Studios President Kevin Feige.
“He’s from a planet called Titan that’s no longer inhabited because of things that he thought he could help prevent, and he was not allowed to do that,” Feige explained. “What he feared most happened, and the planet and everybody on it basically went extinct. He vowed not to let that happen again. He thinks he sees the universe going down the tubes. He thinks he sees life expanding outward unchecked. That will bring ruin, he believes, to the universe and to that life.”
Typically, the loss of loved ones is enough to garner the support of fans and send a hero off on his big adventure -- but we're talking about Thanos, here, and not Spider-Man. However, there remain some similarities. Both individuals take a vow to never let the terrible thing that happened in their past to take place again. After Peter's Uncle Ben was killed, he swore he'd live by the motto, "With greater power, comes great responsibility" while fighting for justice and peace. Thanos lost the inhabitants of Titan -- whether that was by his own actions remains to be seen -- and believes the universe is going down the tubes. The only difference is, instead of trying to save the entire universe, Thanos decides one half will live by sacrificing the other half.