Venom
What are your thoughts about the chaotic anti-hero known as 'Venom'?
Venom is jet black with a large symbol of a white black widow spider on his chest. He has a gaping mouth filled with razor-sharp teeth, a long, lolling tongue, and is often depicted with drooling a green slime-like substance. He is stronger than Spider-Man and his webbing, which the symbiote generates from the mass of its own body, is more durable than Spider-Man's mechanically-generated webs. The symbiote's shapeshifting ability allows Venom to camouflage himself like a chameleon or to assume the likeness of nearly any person. Venom also has the ability to remain undetected by Spider-Man's spider-sense, making him one of Spider-Man's deadliest foes. However, the symbiote is highly vulnerable to fire and high-frequency sound.
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Venom is an odd character. While he is a villain, he doesn't want to harm innocents. That is, if you are not a perceived immoral person in Venom's eyes, you are not attacked or killed. This applies even to the relatives and friends of the person he is after. They are spared and not convicted simply because of who they know. None the less, he is still one of Spider-Mans greatest foes.
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The way I understand Venom is he is supposed to be like the inner thoughts of Peter Parker but about the things he woshed he could do. I think the restraint you're talking about also comes from Peter Parker's thoughts.