The 27-year-old forward featured in Salford Red Devils’ Grand Final defeat by St Helens two months ago, but insisted signing for Tigers is a positive move.
Castleford finished fifth in Betfred Super League this year, two places behind Salford who beat them in the play-offs.
Griffin put pen to paper in July, when Salford were outsiders to qualify for the top five, but has no regrets about the move.
“I want to win trophies in my career and that is why I have come to Castleford,” Griffin stressed.
“Now I have played in the Grand Final I want to go back and win one. We have got a good enough team to do it and, with Daryl Powell steering the wheel, I think we can.”
The pack man, who had a spell on loan at Wakefield Trinity in 2015, added: “It is still early days and pre-season is just about getting the hard work out of the way, then we can start to focus a little bit more on our skill and stuff like that coming up to the friendlies.
“With the players we have got in this team it is inevitable we are going to do something special.”
Griffin reckons his game can move to a new level under Powell.
“I want to work on my skill set a bit more, my passing and stuff like that,” he said.
“Powelly gives the go ahead for the middles to do that – so that is why I have come here, to test myself and improve my game.
“The boys I spoke to couldn’t speak highly enough of Daryl’s coaching standard and his approach to players.
“I knew a little bit about him before but, having worked with him, he is a great bloke and a good coach.”
Tigers were recommended highly by some of Griffin’s former team-mates, which also had an influence. He recalled: “I played with a few of the boys at London, Mike McMeeken and Cooky [Matt Cook].
“I spoke to them before signing and they spoke very highly of the place. I was looking forward to coming here and, so far, I have been proved right in making the decision.”
Griffin is already relishing getting to grips with dual-code super star Sonny Bill Williams who has signed for Tigers’ opening Betfred Super League opponents Toronto Wolfpack.
Toronto will visit the Jungle for Tigers skipper Michael Shenton’s testimonial game on Sunday, January 19 and Griffin predicted: “That will put us in good stead for the first game of the season, we can see what they are about.
“I am looking forward to it and they have obviously made some big signings as well, like Sonny Bill Williams.
“His career speaks for itself – he has played both codes and even boxed and done massive things in all three of them.
“But, at the end of the day, he is just another player in another team and we will approach it like any other game.”