The Fire Boost takes the form of a shield of fire around the user.
In gameplay, the Fire Boost can only be obtained at random from Item Boxes by Blaze and Zavok. As with all other Items, Metal Sonic can also use the Fire Boost if he uses the Steal Item to steal it from the aforementioned users.
When used, it will greatly increase the speed of the user for a short time and surround them in a fiery blaze that damages opponents on contact, resulting in a loss of Rings and being slowed down heavily. Also, when a character is upgraded to level 2, 8 and 14, the Fire Boost will last longer.