You may not be able to play as Gray Fox, but can surely favor is style. Konami has just announced today that a free DLC code will appear in retail copies of Metal Gear Rising Revengeance. Just so happens, this little card will grant you to a new cyborg suit similar to the one worn by Gray Fox.
In addition to acquiring a new suit, Raiden will also have the ability to use and upgrade the Fox Blade carried by Gray. Just be ready to skillfully step into action February 19th, 2013 for Xbox 360 and PlayStation 3. The demo is available now in each marketplace.