Rovers have released Costigan from the last year of his contract, after he left the club citing “personal reasons”.
“I am looking forward to a new challenge both on and off the field and I am thankful to Hull KR for the understanding and professionalism they have displayed in allowing me this opportunity to return to Queensland and play in the Intrust Super Cup,” Costigan said.
Blackhawks coach Kristian Woolf is delighted to have added the PNG international to his ranks.
“Neville is well respected in the playing group and he has a unique strength about him as a competitor,” he said.
“He is a welcome addition to our team and I am sure he will impress when he takes to the field.”