Sonic Crackers, also sometimes referred to as Sonic Stadium (due to the ROM header containing the title Sonic Studium [sic]), is an early Sonic the Hedgehog prototype video game for the Sega Genesis. While it was never officially released in the form of a Sonic the Hedgehog game, the concepts, engine, and various other materials in the prototype were subsequently implemented in the Sega 32X game Knuckles' Chaotix in 1995, and the prototype itself is widely circulated on the internet.