As Marvel's resident genocidal cosmic warlord, it's no surprise that Thanos has sired many children throughout the galaxy. Most of these children aren't significant enough to be spoken about, save for his son, Thane, who tried to kill him with the Phoenix Force before being eternally confined to the mysterious God Quarry. As it turns out, Thanos does have another child way more significant than Thane, and believe it or not, it's the symbiote Carnage, created from the essence of Venom in response to Thanos' infamous act.
In 1991, the famous Infinity Gauntlet storyline by Jim Starlin, George Pérez and Ron Lim had Thanos snap away half of all life in the universe. Even though Thanos didn't need the Infinity Gauntlet to wreak havoc on the cosmos, it still helped him commit one of the most atrocious disasters the universe had ever seen. And an evil version of Reed Richards known as the Maker believes it was due to Thanos' crusade that Carnage was born.
Related: Marvel's Carnage/Ghost Rider Fusion Is Its Sickest Combo Villain Ever
A theory from the Maker in 2018's Venom #20 (from Donny Cates and Iban Coello) states that the symbiote hive mind is capable of sensing impending disasters and responds by rapidly reproducing, bolstering the symbiote population. Since Venom considers himself part of the human hive mind, any threat to Earth is a threat to him and thus he asexually reproduces. So, as Thanos prepared to wipe out 50 percent of the universal population, Carnage was created as Venom instinctually prepared for the worst.
The evil Reed Richards' theory is supported by the timing of Carnage's first appearance and those of several other symbiotes, and many were events spurred by Thanos. Carnage, who has become Marvel's
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