We have already established that Venom cannot defeat Thanos, except under special, highly improbable circumstances. But, as we all know, Venom is not the only Symbiote so it certainly makes sense to compare Thanos with another famous member of Venom’s race – Carnage. Carnage is Venom’s offspring and is known for being much more brutal and bloodthirsty than the Symbiote that took over Eddie Brock. Is that enough to defeat Thanos?
Carnage is not strong enough to defeat Thanos. Although he is more brutal and bloodthirsty than Venom, his powers still aren’t even near Thanos’ level of power and it is because of that that Thanos would be able to deal with Carnage easily, even without the use of the Infinity Gauntlet or some other weapon.
Speaking of Carnage vs Thanos, there’s still a lot to be said. Throughout the rest of this article, we will look at their powers in more detail and see how the fight between Carnage and Thanos would play out.
Carnage and his powers
Cletus Kasady, alias Carnage is a supervillain appearing in the Marvel universe of the publishing house Marvel Comics. Created by writer David Michelinie and artist Mark Bagley, the fictional character first appeared in the Amazing Spider-Man #361 comic book in April 1992. 
Carnage belongs to the line of symbiotes. While the first of them, Venom, is seen as the dark and brutal opposite of Spider-Man, Carnage was presented as a much crazier and bloodier version, hence its red color. Carnage is often considered one of the most powerful symbiotes in the Marvel Universe.
Physical and fighting abilities
Carnage possesses superhuman reflexes and wields greater strength than Spider-Man and Venom combined; he can thus lift (or exert a pressure equivalent to) 80 tons.
Much like Venom, he can scale any surface, regenerate, and escape Spider-Man’s “spider sense”. He could also escape Venom’s ability to hunt down other symbiotes and their hosts.
He can change his physical appearance to mimic that of another person. Much like Venom – whose costume is a definite mass once she’s on her host – he can alter and extend his symbiote’s form at will, allowing him to project thread-like tentacles from the whole body (which replace the webs of Spider-Man and Venom), can also pierce other living beings or form from its symbiote weapons (such as axes or swords).
He is able to see through all parts of his body, the tentacles conveying visual information to Kasady. The latter is also immune to terrestrial diseases, such as cancer, since it is linked to its symbiote. Like all Symbiotes, Carnage is vulnerable to sonic vibrations and fire. However, he later gained resistance to sonic vibrations.
Thanos and his powers
Thanos, the Mad Titan, is a fictional supervillain from the Marvel Universe, known for being one of the most dangerous villains in the large fictional universe. Created by writer and artist Jim Starlin, the Mad Titan first appeared in the Iron Man #55 comic book in February 1973.
Thanos is a mutant (an Eternal with Deviant genes), capable of synthesizing cosmic energy into a number of effects (like all Earth Eternals and Mentors, but not those born on Titan). He is by far the most powerful of the Eternals on Titan.
Psionic abilities and intelligence
His mind is invulnerable to any form of psychic attack, and he has also demonstrated to have telepathic and telekinetic abilities. Through the use of science and witchcraft, Thanos was able to increase his powers significantly. Lady Death, by denying him entry into her realm, also made him immortal.
Despite everything you’ll read about further ahead, his mind remains his most dangerous asset, doomed to bring upon the annihilation of all life. Superhumanly intelligent, he is feared by the entire cosmos. He possesses phenomenal resources and has access to a vast array of advanced weaponry.
In addition to his psionic abilities, he can manipulate the cosmic energy as he pleases to create shields of force, but also to project powerful bursts of energy from his eyes or hands. We have also seen him manipulate matter.
Thanos is likewise blessed with immense physical strength. We do not know clearly the limits of its force, this one not having been measured with precision. However, he has shown that he is able to stand up to Thor and the Thing simultaneously for an extended period of time.
He is therefore likely to have a Class 100 force on the Marvel scale, allowing it to lift (or exert pressure equivalent to) 100 tons, or even more. He is almost invulnerable.
Carnage vs Thanos: Who would win?
As it was the case with Venom, this comparison is difficult only on a superficial level, as the two characters are on a completely different level of power. First of all, we’ve established that Carnage is not even stronger than Venom, which makes this comparison even easier, as it demonstrates that there is a substantial difference in power between Thanos and the Carnage Symbiote.
Sure, the Symbiote who possessed Cletus Kassady is powerful, bloodthirsty and homicidal, but when compared to Thanos and his powers, he doesn’t really stand a chance. While Carnage may be more powerful than a lot of other Symbiotes and even human superheroes, he cannot defeat Thanos, who is an Eternal with a Deviant gene, which makes him even more powerful.
This brings us to the inevitable conclusion that Thanos would win this battle every time. He wouldn’t even need the Infinity Gauntlet or any other weapon to defeat Carnage. The latter would have a slim chance of defeating Thanos if the Mad Titan would grow old and tired, eventually dying from natural causes, but that’s just so improbable we don’t even consider it. Thanos is the clear winner here.