Cletus Kasady: Welcome back, Eddie Brock. It's been a long time. I miss you... so much.
Cletus Kasady: Soon come chaos. Chaos soon come.
Cletus Kasady: Every decision we ever make, who do we leave behind? And how do we leave them? Waiting in the darkness, but the rescuer never comes.
Mrs. Chen: The chocolate delivery hasn't arrived yet.
Venom: NO.
Eddie Brock: We had a deal.
Mrs. Chen: What's gonna happen? You're gonna stop protecting me?
Venom: I am happy to eat Mrs. Chen.
Eddie Brock: No, no. You cannot eat Mrs. Chen.
Mrs. Chen: What?
Eddie Brock: Nothing.
Answer: It is deliberately never shown on screen, so unless it gets answered in a sequel the audience is left to speculate. Mulligan does come into direct contact with Carnage since Cletus is the person who kidnapped him. In addition, the fight between Venom and Carnage takes place all over the church with the pair constantly stabbing, slashing, and bludgeoning each other. A piece of either symbiote could be somewhere in that building. Again, though this is just speculation since it's never shown how Mulligan is infected.
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