The Boost Ring is a rotating ring that allows the player to perform a Speed or Air Boost in the air. When the player jumps into one, the Boost Ring will read out a certain button prompt that usually indicates a recommended route to take: , or ? (in this case, the player can choose either). To perform Air Boost, the player have to press and to perform Speed Boost, the player have to press .
The Boost Ring appeared for the first time in Sonic Rivals. In this game, all of the playable characters can use it.
Sonic Rivals 2
The Boost Ring reappeared in Sonic Rivals 2. It functions exactly like it did in Sonic Rivals, except that they will not show a question mark icon; in such cases, the screen will prompt both and .