JK Simmons reprises his Portal 2 character, Cave Johnson. (He is the best JJJ, though, hope he gets recasted for the new Spider-Man movie)
They are bringing all out with the voice cast, not even the Lego Movie Videogame had the original voices. Gandalf may not be Sir Ian McKellen, but Michael J Fox, Christopher Lloyd, Gary Oldman, JK Simmons, Sean Astin, Peter Capaldi, Jenna Coleman, Elizabeth Banks, Chris Pratt, Bryce Dallas Howard (hopefully Bill Murray did Peter Venkman). Those are some big names.
Can't wait for this game