Joe Wardle has made his switch to Huddersfield permanent following a successful loan spell in 2019.
The deal sees former Giant Jordan Rankin become a permanent Castleford player.
Wardle made 16 appearances for the club in 2019, though ended the season sidelined with injury.
He said: “I’m delighted to be playing with the Giants in 2020 and delighted to confirm I’m playing my Rugby in Huddersfield again.
“I’m excited to be back at a club with my brother and watch his development as well as work hard for the side again.
“After last year, we need to improve and deliver more for the fans and I’m happy that I’ll get the chance to do that.”
Managing director Richard Thewlis said: “The reshaping of the squad continues behind the scenes at a decent pace as this and Ronan’s promotion shows.
“Joe is a key part of Simon’s plans for the 2020 BetFred Super League season and he showed everyone last year how he improved us when he played and was a key senior member of our side.
“He is fully fit after missing the latter games and will start the pre season campaign in mid October.”