Battling cystic fibrosis, Domenic got to wear the suit on Thursday as part of an initiative from the Make A Wish Foundation.
He was put to work by NSW Police Commissioner Andrew Scipione who called Sydney’s own ‘Iron Boy’ to help keep residents safe.
“Iron Boy, we need your help,” the commissioner said.
“Make a Wish reporter Hope Joy has been kidnapped, officers have confirmed that Clark Island has been overtaken by Ultron’s henchmen and Hope Joy has been held captive.
“If I could make one wish, it would be for you to help us Iron Boy.”
The youngster was picked up by police helicopter while playing in a local park in Bringelly and taken to police headquarters for a briefing by the Commissioner.
He was told that Sydney was in trouble and the police needed help.
He was given a specially made suit in the same style as that of his favourite super hero, Iron Man, and battled Marvel nemesis Ultron at the Opera House as a crowd of supporters watched on.
Ms Pace told Make a Wish that Domenic was a very caring child.
“He always wants to know what’s going on around him in the world and how he could help others,” she said.
“I guess the final straw was when he stood up at the dinner table and said ‘I am Iron Boy’, then we pretty much had to go with it from then.”
Downey Jr endorsed the super hero quest on Thursday with a tweet.
The hashtag #IronBoyAU has gone viral on social media.