Sonic 3 and Knuckles is a platformer game developed by Sega. It follows the adventures of Sonic, Tails, and Knuckles as they try to stop the evil Dr. Eggman from taking over the world. The game features fast-paced gameplay, colorful graphics, and an iconic soundtrack. The game introduced many new features, such as the ability to play as Tails, the addition of Knuckles as a playable character, and the Lock-On technology that allowed players to access new content.