Skullwaker on 01 February 2015
I'm pretty sure Sonic Team was at work on one while Boom was in development. It's likely we'll hear about it this E3 and it'll come to PS4, XB1 and Wii U either 2015 or 2016 (which is the 25th anniversary of Sonic). It could be their sendoff for the franchise's physical presence. Unless they really want to be done after the disaster that was Boom.
