Caustic’s plan to gas Solace City has come to an end thanks to Wattson.
Natalie tricked the scientist into disabling the gas and incapacitated him. Wattson decided not to turn him in to the Syndicate, but her mercy isn't going to come cheap: “From now on, doctor... you play by my rules,” she tells him.
The shocking (pun intended) twist took place in a two-part Twitter comic. In the previous episode, Caustic used his gas against Wattson to force her to flee. The comic takes place inside the scientist's twisted version of Water Treatment, where the last episode stopped.
Wattson is trying to disable Caustic's deadly gas that's slowly filling up the room. The two argue about his reasons to attack an entire city, but Wattson appears to succumb to the gas. The scientist worriedly realizes what he's done: “Not you... I never meant this for you,” he says.
Wattson's wounds, however, were just a trick to get the scientist to stop the gas. She gets up and incapacitates Caustic with an electrical shock. “I look forward to you earning my trust again,” she tells him.
The two reunite with the legends but keep their distance from the rest of the cast. Wattson promises not to turn Caustic in to the Syndicate as long as he plays by her rules: “You will be a better man, whether you want it or not.”
Wattson asks if there's anything Caustic wants to tell her—but not about his plans. “Your coughing, your desperate ambition... you owe me the truth.” The scientist tells her not to worry about “this old fool,” which reminds Wattson of her father.
Like the previous episode, the comic helps explain why Wattson still feels warmly about Caustic, despite everything he's done. His cough reminds Natalie of her late father, who presumably died from a disease.
Caustic's cough has been a feature of the character since Apex Legends launched and fans have long speculated that it could be a disease related to his exposure to pesticides or another terminal illness. The comics seem to point toward those theories, at least from Wattson's perspective.
Another link between the two is that Caustic called himself an “old fool,” a callback to Wattson's father. The previous comic showed that Wattson's father told her not to worry about “this doddering old fool” and Caustic's use of a similar sentence helps strengthen the bond between the two.
Caustic and Wattson were close after she entered the Apex Games during the battle royale's second season due to the nearly paternal dynamic between the two. Their relationship took a hit after the events of The Broken Ghost, when Caustic framed Crypto out of jealousy, although Wattson seemed willing to give him another chance. After the latest events, however, the dynamic between the two could shift considerably.