10 Human Comic Book Anti Heroes You Don't Want To Mess With... Ever!
3. Venom
Although the Klyntar itself is extraterrestrial in origin, those who have become Venom are still human. Given recent retcons surrounding the development of the symbiotes too, there's an argument to be made that, although the symbiote was once a corrupting force, it's ultimately the host that bears the most influence.
In the case of Eddie Brock and later Flash Thompson, that influence manifested under morally ambiguous terms. Brock himself did of course start out as one of Spider-Man's greatest adversaries, but over time he cemented himself as an anti-hero through and through, even becoming a symbiote hunter in his later years as the entity known as Anti-Venom, before re-bonding with the suit and becoming Venom once again.
It was Lethal Protector where Venom first had a change of heart though, as Brock faced off against the villainous Life Foundation to ensure the destruction of several symbiote clones. After that, the next true 'anti-hero' to use the Venom symbiote was Flash Thompson, who eventually found himself fighting alongside the Guardians of the Galaxy in space.
Still - while Venom is very much a hero these days, no one wants to cross paths with him. That tongue signals bad things, folks.