Random Most Disturbing Thanos Moments In Marvel Comics (11 items)

(#7) Thanos Slays Gamora After Raising Her

It's already messed up Thanos took a baby Gamora and raised her to be his personal assassin; murdering said adopted daughter is just overkill. Yet that's precisely what the Mad Titan does in Infinity Watch. When her love Adam Warlock sets out to stop Thanos from acquiring the Soul Gems, Gamora accompanies him, ultimately facing off against her adoptive father. He slaps her down and later erases her from existence after completing the Infinity Gauntlet.
(#9) Thanos Kills Half The Universe With A Literal Snap Of His Finger

The Infinitely Gauntlet is one of the most devastating weapons in the Marvel universe When all the Infinity Stones (or Soul Gems, originally) are collected and placed in the Gauntlet, the wielder becomes omniscient, omnipotent, and essentially omnipresent.

Thanos succeeds in this ultimate goal in Infinity Gauntlet, showing off his newfound power by snapping his fingers and instantly eliminating half the living beings in the universe.
(#11) Thanos Takes His Own Life

In the three-part comic book event Infinity, the universe is faced with an even greater threat than Thanos: Annihilus. The Mad Titan has to team up with Adam Warlock to stop the big bad. Things go awry though, and Adam Warlock accidentally traps himself and Thanos in purgatory.

Thanos quickly comes to understand his only way out is death.
(#1) Thanos Dissects His Own Mother

Thanos was separated from his mother, Sui-San, as an infant after she sensed the evil inside him and attempted to kill him. They did not reunite until Thanos was a full-grown adult, and as we learn in his 2013 run, Thanos Rising, their reunion didn't go well for Sui-San. Thanos dissects his mother (who was alive at the beginning of the process) in an attempt to discover an explanation for his abominable nature.
(#3) Thanos Makes Hulk His Leashed Dog

The Thanos comic that began in 2016 goes to some pretty wild places, including a distant future in which Thanos is king of the universe after defeating the Avengers. Most of those Avengers are dead, but not Bruce Banner. He gets the dubious honor or being turned into the Mad Titan's madder hound.
Thanos keeps Hulk in a pit of bones, when he's not on-leash. Among the bones are those of Steve Rogers, the former Captain America who was fed to the Hulk Hound.
(#10) Thanos Ends War Machine And She-Hulk

During a big brawl between Thanos and some Avengers in Civil War II, War Machine inadvertently hits She-Hulk with his missiles. While she's down, Thanos takes advantage, blasting her with his cosmic hands. He then moves on to War Machine himself, punching right through Rhodey's armor and stomach. She-Hulk succumbs to her injuries later.