When it comes to iconic Spider-Man villains, Venom is always somewhere near the top of the list. Likewise, when it comes to Venom foes, Carnage is never forgotten. When symbiotes are mentioned, these two are the characters who spring to mind.
However, the differences between both symbiotes extend beyond their color scheme and origins. They may both belong to the same alien species, but they could not be more distinct. Needless to say, one does not confuse Venom with Carnage.
10 Moral compass
Last year, we got our first look at Sony's Spider-Man spinoff cinematic universe (or something along those lines) with the release of Venom. The movie very clearly places the symbiote in a similar position to the likes of Deadpool or The Punisher. An anti-hero, so to speak.
Venom stops evil, but he is still a monstrous man-eater. The symbiote has a longer villainous history in the comics, but his anti-heroic stance still stands. Carnage, on the other hand, is a villain through and through. Ever since his birth and subsequent bond with Cletus Kassady, the red-tinted symbiote had done little more than kill anyone in his way.
Venom may be the lesser of two evils in this equation, but Carnage wins when it comes to loyalty. Carnage is never just the symbiote, but the amalgamation of both it and its host, Cletus Kassady. This crazed serial killer was Carnage's first-ever host and they have since remained inseparable. There were a few times when the symbiote left Kassady to find other possible hosts, but he always ended up returning. Venom, on the other hand, is a forever unsatisfied creature.
He first temporarily bonded with Deadpool. Then he swung around with Peter Parker, who rejected him, before moving to Eddie Brock. This was then followed by countless others. Now, Venom lives in a constant change between Peter, Eddie, and Flash Thompson. Carnage always refers to him and Cletus as "I" because both symbiote and host are one. Venom's constant use of "we" shows his constant internal struggle with any host he bonds with.
All symbiotes have a wide array of different powers and abilities, and although many are similar, there are clear differences both in specific abilities and in overall power. In terms of sheer strength, Carnage's first encounter was against a Venom/Spider-Man team-up, where he proved himself to be stronger than his two foes combined. Carnage can grow even stronger by feeding off negative emotions around him. Speaking of Spider-Man, there's a reason why the black symbiote is so associated with Peter Parker.
When he bonded with him, Venom managed to imprint spider-powers on to himself, and he's been using them ever since. Carnage, on the other hand, relies more on claws, fangs, and tentacles as opposed to black webs.
The connection between both symbiotes is a lot bigger than most people realize. Venom was created by an ancient god named Knull, along with dozens of other symbiotes. After escaping Knull's control, Venom was found by a Kree soldier and fought in the Kree-Skrull War. It was then freed and its memory erased. The symbiote remained alone on the planet that would become the stage for the Secret Wars storyline, where he was discovered by Spider-Man and taken to Earth.
Carnage's history is easier to understand seeing as he comes from a humble American prison cell. When Eddie Brock was incarcerated, he was put in the same cell as Cletus Kasady. Venom decided to rescue his host from prison and, although he succeeded, he unknowingly left a spawn behind (the symbiote equivalent of giving birth). The spawn immediately latched on to Cletus, creating Carnage.
6 Relationship to Spider-Man
During a time when Venom was still unknown, and thus not considered a "bad guy", he bonded with one of his first-ever hosts, Spider-Man. Disguising himself as just a black costume, he helped Peter fight crime and enjoyed being a hero. Unfortunately, when the hero found out his costume was actually a living creature who wanted to bond with him forever, Peter rejected it in disgust and forced the symbiote out of him by exploiting his weakness to sound.
This betrayal forever left Venom with an intense hatred of Spider-Man. Carnage's feelings towards Spider-Man are a whole lot less complicated, but the wallcrawler was still the first hero Carnage fought and the one he has faced the most.
Many recall Venom's first on-screen appearance in Spider-Man 3 (even if many choose to forget). Eddie Brock stumbled upon the black symbiote, became a villain, and had a final battle against Peter Parker. What's interesting is the way he was defeated, which is pulled straight from the comics. To release Eddie from the symbiote, Spider-Man surrounds his foe in metal tubes and starts banging them together to create a loud, thunderous noise. Besides sound, Venom's other kryptonite is heat. This normally applies to all symbiotes, but Carnage is far from normal.
If there's one thing to note about Carnage is that he is not a complicated creature at all. That is, at any given time, it's clear to anyone and anything what he wants and what he's feeling. The second this symbiote was introduced into the world, it immediately bonded with a crazed, bloodlust, serial killer. Therefore, with no other memory than that of Cletus Kassady's, Carnage became a similarly crazed, bloodlust murderer, who takes great pleasure in killing.
Venom, on the other hand, is as complicated as can get. His first host, a genocidal maniac from another planet, created in him an aggressive, monstrous personality. However, all his subsequent hosts have the effect of altering his personality.
Physically bonding with other creatures is second nature to all symbiotes, Venom and Carnage included. The latter's loyalty to Cletus Kassasdy has been previously mentioned, but that didn't stop the symbiote from shaking things up a little from time to time with other hosts. John Jameson (J Jonah's son), Ben Reily (Scarlet Spider), and the Silver Surfer were all short-lived, yet significant, hosts of his. A more durable body was that of Dr. Karl Malus, who, along with the symbiote, became the Superior Carnage.
His last non-Kassady host was arguably his greatest. After bonding with Norman Osborn, the combination gave birth to a terrifying villain known as the Red Goblin. On the other side of the spectrum is Venom, who seems as if he's bonded with everyone on the planet. Even then, his preferred hosts will always be Spider-Man, Eddie Brock, and Flash Thompson.
2 Physical contrast
Venom and Carnage may be father and son, but they are both very different physically. Apart from their monstrous eyes, and shark-like teeth, they really don't look alike. Obviously, the color scheme is what first comes to mind. While one wears a dark, Batman-like body, the other presents itself in ultra-bright red. The most interesting aspects about their looks though, is how they represent the symbiotes themselves.
Venom, for example, is not all black, as he has a permanent white spider symbol stapled to his chest. This is a clear reference to his strong connection to Spider-Man. Carnage, on the hand, is red all around, but he has a more unstable, and much less solid body than that of his father. With red strings dangling from everywhere, Carnage comes off as an unpredictable, dangerous lunatic...which he is.
Throughout Venom's confusing hero/villain journey, one thing he has done is join already established groups. Some of them quite famous. During his heroic stints, he has been called a Guardian of the Galaxy, a S.H.I.E.L.D agent, and even an Avenger. However, working as part of a team isn't what makes him a "good guy" because he has likewise exerted his evil side alongside the dreaded Sinister Six, and the villainous Thunderbolts.
Carnage wants none of this. He and Cletus are one, and they work alone. Even though foes have teamed up against him, he always goes into battle solo. He once led a murder spree through New York City with a few other low-lives, but even that was short-lived and unimportant to him. At the end of the day, his allegiance lies only with Cletus Kassady and himself.