"The way you talk to me, the condescending attitude, the way you're, like, 'Rub two brain cells together. The way you would always tell me, like, 'Yeah, your brain don't work so well.''
Ariana hit back, saying Sandoval "made that f---ing joke." Sandoval doubled down, claiming Ariana was "always always telling me that I'm dumb" throughout their relationship.
Katie Maloney chimed in, calling Sandoval "crazy," while Ariana added that her ex is "literally delusional."
"I'm not," Sandoval said. "I'm not dumb either."
Ariana argued that she "never" called Sandoval "dumb" until the reunion.
"I've never told you you were dumb," she said, adding, "I never said you were dumb until today. 'Cause you're acting dumb today."
"I'm gonna use your tactic that you told me about about filming this show -- is that if someone’s saying something wrong about you, never let them finish a sentence," she fired at her ex.
Sandoval claimed it wasn't his tactic, but Ariana's. "That's not what I said, I said you need to correct them. That was your tactic. That was your tactic, motherf---er. You said these girls like to spread propaganda."
As Ariana and the ladies reacted to Sandoval's claim about them, Lisa Vanderpump was shocked that Sandoval appeared to call his ex a "motherf---er."
"Did you just call her motherf---er?" she asked Sandoval, who casually shrugged in reply.
In March, news broke that Sandoval and Ariana had split after nine years together following the latter's discovery of the former's month-long affair with their co-star Raquel Leviss.
After the affair came to light, fans have been watching Season 10 of "Vanderpump Rules" with a new lens as signs of Sandoval and Raquel's secret romance -- as well as problems in Sandoval and Ariana's relationship -- began to show.
In an April episode, Sandoval expressed concerns about his relationship with Ariana, noting that he believed his then-girlfriend questioned his intelligence.
"It hurts my feelings because the person I love thinks I'm dumb or, like, annoying," he said in a confessional. "It definitely pulls in the question, like, whether Ariana and I are right for each other."
You can watch the "Pumped Up" editions of Parts 1 and 2 of the "Vanderpump Rules" reunion on Peacock now. The three-part reunion concludes next Wednesday.