They are joined by Senior Academy players Adam Scott of Hull and James Endersby of Leeds.
Twenty three year old Mbu was enthusiastic about the move: "My main aim for the season is getting the lads together as a group and as a team. I hope my new team mates will benefit from my experiences in Super League and equally, I will be looking to learn from them."
The Lakeside Stadium, Doncaster's new ground for next season, was quoted as one of the reason's Rikki Sheriffe followed Mbu to the Lakers: "Before every season I set myself a personal target of scoring a try every game and looking at the new stadium, I can see that it definitely has a runners pitch so I am really looking forward to playing there."
The club has also announced that they will return to their traditional colours of Blue and Gold as their home kit for next season.
Lakers Chairman, John Wright said: "We have decided to revert back to tradition and go with the colours most Rugby League supporters recognise as Doncaster. In order to keep an identity which is different we will stick with Red and Black as the away strip and use Red And Black on the website and corporate literature as it gives a much more pronounced image. I apologise to those supporters who didn't like the change last year, but can only say it was done with the best intentions."