Dario Cerulli was stationed on the Axiom Ordnance complex on Bukari V. He was in charge of organizing the advertising campaign for the new Warhound combat walker, and served as a handler for the famed director of the commercial, Ottmar Drenthe. He met with Drenthe as he arrived in the facility, and showed him around the factories. During their tour, they ran into a worker protest, which Cerulli was upset by. He called security, and they violently suppressed the protest. Cerulli apologized to Drenthe, saying they wanted more money when Axiom didn't have it to give.
Later, Drenthe wandered into Cerulli's office, where they discussed the history of the Warhound and the retirement of its creator, Yakov Iliev. Cerulli then revealed that the Warhounds used in the demonstration would be piloted, which worried Drenthe as he had been paid by a consultant named Eli to rig the demonstration and destroy the Warhounds. This convinced Drenthe to betray both Axiom and Eli, and side with Ayla and her protesting workers to fully complete the demonstration and help them overthrow Axiom.
The next day, the demonstration went off without a problem in spite of Eli's sabotage. Cerulli was in charge of the voiceover, announcing the weapons systems and capabilities of the Warhounds. Even as Eli tried to shut down the demonstration and kill Drenthe, Cerulli's voiceover kept going. Eventually, Ayla and her workers used the Warhounds to turn on and destroy Axiom's security forces, and start leveling the structures in Axiom's executive complex. Drenthe escaped the planet before he could discover Cerulli's fate.