While staying in Monaco during a flight scale, Maria escaped from her bodyguards at a casino, where she deliberately lost large sums of money at baccarat and was escorted from the premises.

Howard Stark (who owned the casino) noticed herself being forcefully escorted by her bodyguards and they followed her back to her hotel room.

Howard secretly programmed the Mistress AI that controlled the Arsenal robots with Maria's brain patterns.

[1] On the Ides of March, Maria and Howard were killed in a car accident arranged by the Roxxon Oil Company.

[7] At Port Authority, Iron Man catches up to the duplicates of Howard and Maria, who are instructed not to leave the safety of Brain Tower.

When Tony uses the Thirteenth Floor to reach the Stark Space Station and confront Arno, Arsenal and Motherboard fight his allies until the arrival of the Extinction Entity.

[11] While what has been depicted is retconned as an in-universe fictional TV show about Iron Man's life, the actual Ultimate version of her character is briefly mentioned by her other son Gregory Stark when he jokingly says how he "came out of [Maria] before [Tony]".