Carnage

After a battle with Styx where Venom was presumed dead, former host Eddie Brock was put in a prison for "normal" humans. His cell mate was Cletus Kasady, psychotic murder serving eleven life sentences. However, the symbiote was not dead but incapacitated for a time. Eventually it rebounded with Eddie and the pair broke out. However, in the hurry it left behind its spawn which bounded with Kasady to create Carnage. Over months, Carnage went on a killing spree and would leave the message "Carnage Rules" written in blood. Eventually Carnage and Spider-Man fought and spider-man was defeated. Realizing Carnage was another Symbiotic powered villain, Spider-Man enlisted the help of Venom, who had retired to a deserted island, to defeat Carnage. After enlisting Venom's aid against Carnage, Spider-Man later used loud noises in an attempt to defeat both father and son.

The symbiote has been "killed" at least twice. Once mentioned above and later when Venom, in an attempt to end the threat of Carnage once and for all, ate its spawn. However, both times they have been replaced. He found a copy of his suit in the Negative Zone and in the "Maximum Carnage" Arc it is revealed that during his first fight with Venom and Spider-Man that the symbiote used a cut on Kasady to alter his metabolism to create a perfect copy of the symbiote. This would mean that Kasady has not wore the original for a very long time, however when he gives birth to his son Toxin, Venom claimed the spawn was his grandchild. Which would indicate that Kasady has been wearing the original all along.

The symbiote has a considerably stronger bond with Kasady then its father has with its hosts. This is indicated by the fact that Kasady has predominantly used the term "I", as apposed to his father's use of "we". However, even though the bound between host and symbiote is strong, it had left Kasady several times to find more powerful hosts. It's bounded with John Jameson, the Scarlet Spider (at the time referred to as Spider-Carnage) and the Silver Surfer (forming The Carnage Cosmic) but it always ended up back on Kasady. Eventually it and Kasady met their end while escaping "The Raft", a prison for super powered people. He was ripped apart by Sentry in outer space.

It turns out both the symbiote and Kasady survived, and although initially bonded to Tanis Nieves, eventually bonded back to Kasady. Carnage plans to wreak havoc across the US.