Earlier today, David Petersen shared this:
— David Petersen (@mouseguard) December 28, 2015
The book is said to include commissions, Free Comic Book Day covers & promotions, plus 30 pieces that have never been collected in the sketchbooks. The price point is a reasonable $15.00 so if you're a fan of Mouse Guard, which I am, this is a great investment. For more information visit Petersen's website here.