Sonic & Knuckles — controlling the game character, the player goes through various levels, the structure of which is labyrinth-like and includes many steep slopes and loops, with the help of which the characters can accelerate to high speed. The main enemies in the game are robots — badniks, different in appearance and weapons. To attack, the player character rolls up into a ball — either attacking the enemy while jumping, or accelerating in place and performing a high-speed roll attack called a spin dash. The character's life force is controlled by golden rings, which are scattered in large quantities throughout the levels.