'If Spiderman 4 wasn't canceled, i think this could of been a good idea..
After defeating venom, an unsuspected meteor hits beside a prison, having this deadly symbiote split out of the meteor and breaking into the prison. The symbiote then bonds with serial killer Cletus Kassady, causing him to transform into a big vicious creature and escaping. Kassady is now taken over by the symbiote altering his thoughts to cause destruction and carnage throughout the world. When Spiderman attempts to defeat Kassady, he realizes the symbiote is too powerful to beat, then remembers Dr. Connors still has a sample of the venom symbiote. Later on, Peter Parker then goes to Dr. Connors and lies to him saying hes using the sample for an experiment, before he leaves to defeat Kassady, he releases the symbiote and has no choice but to let the symbiote bond with him to defeat him.